|
'69 Olds 442 Idle Problem
Some metal content, (barely)...This started last spring actually when
I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). The distributor bearings were also in dire shape so the dist was replaced. It started and ran well now, but idled poorly. I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. Everything else looked okay. The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. The engine had 250K plus miles. He asked me if I wanted to do it, but I d too many irons in the fire. So he took it to a decent local garage where they yanked the engine for a total rebuild. Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. Well, here is where it gets weird. It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. The cam timing and ignition timing are checked and rechecked. Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. On many manifolds this area is open anyway. I could TIG it up, but I guessing this would be a waste of time. None of the carbs tried may have been jetted right for this engine. Any Quadrajet/Olds experts out there care to weigh in? |
'69 Olds 442 Idle Problem
"oldjag" wrote in message ... Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. If I had to guess, I'd start with the ignition, if you find the idle mixture is about right - with the higher compression the ignition is more critical - put the stock Dist back, new plugs and new wires (and dist cap, etc) and see if it's better. |
'69 Olds 442 Idle Problem
If I had to guess, I'd start with the ignition, if you find the idle
mixture is about right - with the higher compression the ignition is more critical - put the stock Dist back, new plugs and new wires (and dist cap, etc) and see if it's better. I'll second the motion. My old man had a saying for old cars, "Its always the ignition, when you're sure its something else, its in the ignition". Plus you can see the other shop has beat carburation and valve timing to death with no effect. I'd tell this guy, strickly time and materials, no promises. Or, he'll just be mad at you, also. Karl |
'69 Olds 442 Idle Problem
"Bill Noble" wrote in message ... "oldjag" wrote in message ... Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. If I had to guess, I'd start with the ignition, if you find the idle mixture is about right - with the higher compression the ignition is more critical - put the stock Dist back, new plugs and new wires (and dist cap, etc) and see if it's better. As crazy as it sounds, I would swap out the coil, even with a used one, just to check. I have seen ignition coils do some really weird things. Please let us know what you find out. I love to hear stories of mechanical puzzles. Seem far to many of them. |
'69 Olds 442 Idle Problem
oldjag wrote:
SNIP Any Quadrajet/Olds experts out there care to weigh in? All carbs tested could not get a good idle. Any 4 BBL carb should get a smooth idle on a V-8, as jets do not affect the idle circuit, unless the power valve is opening. Check Harmonic balancer for slippage. (i.e. is TDC really TDC?) What kind of gas is he using? My 442 I used to have had 10.5:1 compression, and would knock like hell unless using at least 96 octane. Wrong fix is retard initial timing, and delay mechanical advance. Causes low vacuum, poor idle. How is the vacuum advance hooked up, ported or direct? What idle speed are the readings obtained from? Should be about 625-650 rpm in park, and about 600 in drive. -- Steve Walker (remove wallet to reply) |
'69 Olds 442 Idle Problem
"oldjag" wrote in message ... Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). The distributor bearings were also in dire shape so the dist was replaced. It started and ran well now, but idled poorly. I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. Everything else looked okay. The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. The engine had 250K plus miles. He asked me if I wanted to do it, but I d too many irons in the fire. So he took it to a decent local garage where they yanked the engine for a total rebuild. Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. Well, here is where it gets weird. It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. The cam timing and ignition timing are checked and rechecked. Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. On many manifolds this area is open anyway. I could TIG it up, but I guessing this would be a waste of time. None of the carbs tried may have been jetted right for this engine. Any Quadrajet/Olds experts out there care to weigh in? Dump the Quadrajet. |
'69 Olds 442 Idle Problem
In article , oldjag wrote:
Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. [...] I'm sure you simply omitted to mention it, but I didn't see any indication in your post that the spark plugs were replaced... One other thing, kind of a long shot, but I've seen it happen befo when the other shop finished with the rebuild, did they get the plug wires back on properly? Incorrect firing order would easily account for the idle being worse, and power way down. |
'69 Olds 442 Idle Problem
oldjag wrote:
Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). The distributor bearings were also in dire shape so the dist was replaced. It started and ran well now, but idled poorly. I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. Everything else looked okay. The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. The engine had 250K plus miles. He asked me if I wanted to do it, but I d too many irons in the fire. So he took it to a decent local garage where they yanked the engine for a total rebuild. Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. Well, here is where it gets weird. It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. The cam timing and ignition timing are checked and rechecked. Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. On many manifolds this area is open anyway. I could TIG it up, but I guessing this would be a waste of time. None of the carbs tried may have been jetted right for this engine. Any Quadrajet/Olds experts out there care to weigh in? Two thoughts: Cracked manifold can lean the mixture, as it is part of the PCV circuit. It would have the same effect as a PCV valve stuck open, or a cracked hose to PCV. It does have a PCV valve, right? And an air inlet in the other valve cover? Camshaft - if it has any more overlap than stock, the idle mixture can go rich. We used to have to crack the secondaries a bit on Holleys to compensate for a hotter cam. Yours may not be hot enough to matter, and the secondary butterflies may not have an adjustment. Look at the overlap specs on the cam, and consider going back to stock cam. Vac 12 inches - at what vacuum does the power enrichment kick in on the Qjet? It's possible it is set to something close to the average vacuum, and just dribbling additional fuel, but not enough to raise the avg mixture on your A/F meter. |
'69 Olds 442 Idle Problem
In article
, oldjag wrote: Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). The distributor bearings were also in dire shape so the dist was replaced. It started and ran well now, but idled poorly. I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. Everything else looked okay. The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. The engine had 250K plus miles. He asked me if I wanted to do it, but I d too many irons in the fire. So he took it to a decent local garage where they yanked the engine for a total rebuild. Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. Well, here is where it gets weird. It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. The cam timing and ignition timing are checked and rechecked. Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. On many manifolds this area is open anyway. I could TIG it up, but I guessing this would be a waste of time. None of the carbs tried may have been jetted right for this engine. Any Quadrajet/Olds experts out there care to weigh in? Hmmm... just for snorts & giggles, take a look at the harmonic balancer. Has deteriorating rubber allowed the outer ring (along with the timing mark) to slip around? Your low manifold vacuum that improves with advanced ignition timing is what makes me suspicious. Slipped balancers are not unheard of, especially on older engines. If this should be the case, there are places around that rebuild them for a lot less than new, ask the folks at your machine shop. Good luck, let us know how it comes out. Erik |
'69 Olds 442 Idle Problem
On Aug 27, 1:58*am, oldjag wrote:
Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. *Towed the car to my home garage a block away. *Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). *The distributor bearings were also in dire shape so the dist was replaced. *It started and ran well now, but idled poorly. *I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. *Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. *Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. * *Everything else looked okay. *The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. *The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. *The engine had 250K plus miles. *He asked me if I wanted to do it, but I d too many irons in the fire. *So he took it to a decent local garage where they yanked the engine for a total rebuild. *Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. *Well, here is where it gets weird. * It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. *So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. *The cam timing and *ignition timing are checked and rechecked. *Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. *Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. *No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). *The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. *I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. *On many manifolds this area is open anyway. *I could TIG it up, but I guessing this would be a waste of time. *None of the carbs tried may have been jetted right for this engine. *Any Quadrajet/Olds experts out there care to weigh in? Stock carb, and the carbs they tried, could all have worn throttle shaft bushings. It's easy to overlook this vacuum leak, and it also allows the throttle plates to randomly open-and-close a bit as it idles. A Qjet in good shape is a *great* carb. Dave |
'69 Olds 442 Idle Problem
" Hmmm... just for snorts & giggles, take a look at the harmonic balancer. Has deteriorating rubber allowed the outer ring (along with the timing mark) to slip around? Your low manifold vacuum that improves with advanced ignition timing is what makes me suspicious. Slipped balancers are not unheard of, especially on older engines. If this should be the case, there are places around that rebuild them for a lot less than new, ask the folks at your machine shop. Good luck, let us know how it comes out. on most cars, the damper is pinned, though it can shift a little - the place I use for rebuilding (they do good work) is "DameprDoc" |
'69 Olds 442 Idle Problem
Steve Lusardi wrote:
The key is low idle vacuum. You have a leak or you have lost index on the balancer and TDC needs to be verified. Don't overlook the brake vacuum booster, throttle shafts on the carb,PVC valve or EGR valve leakage. Steve No EGR on that one, though the aluminum manifold may have provision for one. "oldjag" wrote in message ... Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). The distributor bearings were also in dire shape so the dist was replaced. It started and ran well now, but idled poorly. I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. Everything else looked okay. The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. The engine had 250K plus miles. He asked me if I wanted to do it, but I d too many irons in the fire. So he took it to a decent local garage where they yanked the engine for a total rebuild. Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. Well, here is where it gets weird. It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. The cam timing and ignition timing are checked and rechecked. Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. On many manifolds this area is open anyway. I could TIG it up, but I guessing this would be a waste of time. None of the carbs tried may have been jetted right for this engine. Any Quadrajet/Olds experts out there care to weigh in? |
'69 Olds 442 Idle Problem
"Steve Lusardi" wrote in message ... The key is low idle vacuum. You have a leak or you have lost index on the balancer and TDC needs to be verified. Don't overlook the brake vacuum booster, throttle shafts on the carb,PVC valve or EGR valve leakage. Steve if the idle is irregular the vacuum will be low, whether the irregularity is due to ignition problems, valves, a leak, or something else. To me, at least, on that vintage engine, the sound of the engine is very distinct if it is fuel starved, or fuel rich, and it changes if the timing (ignition timing) is off also. Of couse the descriptions here are text only and don't include sound files, but here's my impression lean - harsh sound rich - soft labored sound advanced - sharp stacatto sound retarded - labored and weak sound take a thin hose, hold one end near your ear and move the other end around the manifold, carb, plugs, etc - listen and see if you hear leakage |
'69 Olds 442 Idle Problem
On Thu, 27 Aug 2009 07:30:25 -0500, "Karl Townsend"
wrote: If I had to guess, I'd start with the ignition, if you find the idle mixture is about right - with the higher compression the ignition is more critical - put the stock Dist back, new plugs and new wires (and dist cap, etc) and see if it's better. I'll second the motion. My old man had a saying for old cars, "Its always the ignition, when you're sure its something else, its in the ignition". Plus you can see the other shop has beat carburation and valve timing to death with no effect. I'd tell this guy, strickly time and materials, no promises. Or, he'll just be mad at you, also. Karl Find a "high energy"distributor from a later model olds and put it in. Guaranteed adequate spark. Then go from there. If 60,000+ volts won't fire the plugs, nothing will |
'69 Olds 442 Idle Problem
On Thu, 27 Aug 2009 19:59:24 -0700, "Steve Lusardi"
wrote: The key is low idle vacuum. You have a leak or you have lost index on the balancer and TDC needs to be verified. Don't overlook the brake vacuum booster, throttle shafts on the carb,PVC valve or EGR valve leakage. Steve Don't overlook the vacuum break for the automatic choke either. VERY common failure point on '60s QJ carbs. If the diaphragm is leaking you will NOT get it to idle smoothly. PERIOD. First thing I would do is verify compression. A good leakdown (aircraft type) tester would be handy as well. Then VERIFY ignition timing mark (damper) - and if compression is even but low verify valve timing. A good ignition scope and someone who knows how to read it can verify both primary and secondary ignition - I'd put a NEW set of the proper AC plugs in. With a hot cam, the proper plug will be COLDER than original. Then check or replace the wires and coil. My preference would be to put in a later model high energy (electronic) distributor with the coil built in. and 8mm mag-core wires Then check ALL vacuum devices for leaks. Block the lines to the heater controls for testing purposes, and use a "mighty-vac" to check all diapragms etc. Feed a bit of propane through a hose to all suspected vac leak areas (throttle shafts, base gaskets, etc that cannot be verified mechanically.. Unless the replacement cam is "wild" getting it to idle should not be hard. Getting it to PERFORM can be more difficult. "oldjag" wrote in message ... Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). The distributor bearings were also in dire shape so the dist was replaced. It started and ran well now, but idled poorly. I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. Everything else looked okay. The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. The engine had 250K plus miles. He asked me if I wanted to do it, but I d too many irons in the fire. So he took it to a decent local garage where they yanked the engine for a total rebuild. Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. Well, here is where it gets weird. It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. The cam timing and ignition timing are checked and rechecked. Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. On many manifolds this area is open anyway. I could TIG it up, but I guessing this would be a waste of time. None of the carbs tried may have been jetted right for this engine. Any Quadrajet/Olds experts out there care to weigh in? |
'69 Olds 442 Idle Problem
by the way, a friend used to drive a olds 442 - a bit older than 69 - there
is nothing like shifting into 4th and burning rubber at 120mph to prove that you have way too much horsepower. |
'69 Olds 442 Idle Problem
The key is low idle vacuum. You have a leak or you have lost index on the balancer and TDC needs to be verified. Don't overlook
the brake vacuum booster, throttle shafts on the carb,PVC valve or EGR valve leakage. Steve "oldjag" wrote in message ... Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). The distributor bearings were also in dire shape so the dist was replaced. It started and ran well now, but idled poorly. I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. Everything else looked okay. The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. The engine had 250K plus miles. He asked me if I wanted to do it, but I d too many irons in the fire. So he took it to a decent local garage where they yanked the engine for a total rebuild. Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. Well, here is where it gets weird. It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. The cam timing and ignition timing are checked and rechecked. Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. On many manifolds this area is open anyway. I could TIG it up, but I guessing this would be a waste of time. None of the carbs tried may have been jetted right for this engine. Any Quadrajet/Olds experts out there care to weigh in? |
'69 Olds 442 Idle Problem
On Thu, 27 Aug 2009 20:59:09 -0700, the infamous JR North
scrawled the following: Kudus for all the good replies. Huh? Y'mean "kudos", Jace? vbg http://www.wildlife-pictures-online....-0010_blog.jpg I vote for 2 problems: 1. Problem started after 1st ditributor replacement: Timing is off. Going through several mechanics-must be basic, thus unfound. Verify TDC #1-ck balancer This is one I'd never seen while wrenching, but I have heard of it happening. 2. Vacuum leak-definately. Big one, too. I vote for brake booster. HVAC -not enough to materially affect idle. Intake manifolds replaced; unlikely but possible leaks bottom side of intake runners at head ports. PCV valve wide open-probable. Yeah, vacuum leaks are #2 for rough or no idle after clogged idle jet circuits (in unrebuildable Holleys. ;) I didn't see many open brake boosters but saw lots of loose or split vacuum hoses, missing caps, misrouted vacuum lines, and open EGR valves in later models. I'd vote for the leak at the new Edelbrock intake. I saw that a whole lot. BTW: aint noth'n wrong with Qjets. Yeah, I much preferred Rottenchesters to Holleys for GM products. -- A striking fact of the last two years of financial trouble is how accountability has differed in the public and private spheres. On Wall Street and across the country, decades-old firms have failed, fortunes have vanished, and some former captains of finance face jail or fines. In Washington, meanwhile, most regulators and Members of Congress remain on the job, often with enhanced power. -WSJ "Bernanke's Second Chance" 26aug09 |
'69 Olds 442 Idle Problem
Bill Noble wrote:
by the way, a friend used to drive a olds 442 - a bit older than 69 - there is nothing like shifting into 4th and burning rubber at 120mph to prove that you have way too much horsepower. .....or not enough tire! 14" tires on 7" rims. Polyglass GT bias-plies. |
'69 Olds 442 Idle Problem
JR North wrote:
2. Vacuum leak-definately. Big one, too. I vote for brake booster. HVAC -not enough to materially affect idle. Intake manifolds replaced; unlikely but possible leaks bottom side of intake runners at head ports. When the heads were rebuilt, did they surface them? A deep cut or several light cuts can leave the manifold mismatched to the vee formed by the heads. If you end up pulling the manifold, check for port matching. Look at the gaskets you remove and try to determine if they were sealing all around each port. |
'69 Olds 442 Idle Problem
On Thu, 27 Aug 2009 18:05:34 -0700, "Bill Noble"
wrote: by the way, a friend used to drive a olds 442 - a bit older than 69 - there is nothing like shifting into 4th and burning rubber at 120mph to prove that you have way too much horsepower. Nope - 80's Grand Cherokee with a Cadillac 502. That'll rattle your fillings... -- Bruce -- |
'69 Olds 442 Idle Problem
|
'69 Olds 442 Idle Problem
On Fri, 28 Aug 2009 10:26:03 -0500, RBnDFW
wrote: Bill Noble wrote: by the way, a friend used to drive a olds 442 - a bit older than 69 - there is nothing like shifting into 4th and burning rubber at 120mph to prove that you have way too much horsepower. ....or not enough tire! 14" tires on 7" rims. Polyglass GT bias-plies. More correctly, Bias-belted |
'69 Olds 442 Idle Problem
On Wed, 26 Aug 2009 22:58:49 -0700 (PDT), oldjag
wrote: Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). The distributor bearings were also in dire shape so the dist was replaced. It started and ran well now, but idled poorly. I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. Everything else looked okay. The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. The engine had 250K plus miles. He asked me if I wanted to do it, but I d too many irons in the fire. So he took it to a decent local garage where they yanked the engine for a total rebuild. Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. Well, here is where it gets weird. It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. The cam timing and ignition timing are checked and rechecked. Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. On many manifolds this area is open anyway. I could TIG it up, but I guessing this would be a waste of time. None of the carbs tried may have been jetted right for this engine. Any Quadrajet/Olds experts out there care to weigh in? Transmission modulator? |
'69 Olds 442 Idle Problem
"oldjag" wrote in message Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). The distributor bearings were also in dire shape so the dist was replaced. It started and ran well now, but idled poorly. I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. Everything else looked okay. The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. The engine had 250K plus miles. He asked me if I wanted to do it, but I d too many irons in the fire. So he took it to a decent local garage where they yanked the engine for a total rebuild. Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. Well, here is where it gets weird. It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. The cam timing and ignition timing are checked and rechecked. Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. On many manifolds this area is open anyway. I could TIG it up, but I guessing this would be a waste of time. None of the carbs tried may have been jetted right for this engine. Any Quadrajet/Olds experts out there care to weigh in? It looks like you have already tried all the things that have been suggested by the guys responding except for one: The crankshaft vibration damper. The outer ring must have rotated slightly giving you late ignition timing. My vote goes with those that said that that was the problem......phil |
'69 Olds 442 Idle Problem
It looks like you have already tried all the things that have been suggested by the guys responding except for one: The crankshaft vibration damper. The outer ring must have rotated slightly giving you late ignition timing. My vote goes with those that said that that was the problem......phil add another vote for this, check the timing mark on the balancer. Is the pointer welded or bolted to the front of the motor, I've seen the wrong one installed on the bolt on type. BTW, I've never seen or heard of a stock factory damper that was pinned, maybe a high performace aftermarket, but not an OEM. Thank You, Randy Remove 333 from email address to reply. |
'69 Olds 442 Idle Problem
"oldjag" wrote in message Some metal content, (barely)... This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. Towed the car to my home garage a block away. Hey there oldjag, there's a lot of guys waiting to hear what you came up with to fix this idle problem! Let us know, eih? please........phil |
'69 Olds 442 Idle Problem
|
'69 Olds 442 Idle Problem
On Aug 27, 11:04*am, RBnDFW wrote:
oldjagwrote: Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. *Towed the car to my home garage a block away. *Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). *The distributor bearings were also in dire shape so the dist was replaced. *It started and ran well now, but idled poorly. *I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. *Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. *Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. * *Everything else looked okay. *The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. *The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. *The engine had 250K plus miles. *He asked me if I wanted to do it, but I d too many irons in the fire. *So he took it to a decent local garage where they yanked the engine for a total rebuild. *Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. *Well, here is where it gets weird. * It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. *So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. *The cam timing and *ignition timing are checked and rechecked. *Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. *Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. *No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). *The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. *I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. *On many manifolds this area is open anyway. *I could TIG it up, but I guessing this would be a waste of time. *None of the carbs tried may have been jetted right for this engine. *Any Quadrajet/Olds experts out there care to weigh in? Two thoughts: Cracked manifold can lean the mixture, as it is part of the PCV circuit. It would have the same effect as a PCV valve stuck open, or a cracked hose to PCV. * * It does have a PCV valve, right? And an air inlet in the other valve cover? Camshaft - if it has any more overlap than stock, the idle mixture can go rich. We used to have to crack the secondaries a bit on Holleys to compensate for a hotter cam. Yours may not be hot enough to matter, and the secondary butterflies may not have an adjustment. * * *Look at the overlap specs on the cam, and consider going back to stock cam. Vac 12 inches - at what vacuum does the power enrichment kick in on the Qjet? * It's possible it is set to something close to the average vacuum, and just dribbling additional fuel, but not enough to raise the avg mixture on your A/F meter. Yeah that's one of the concerns I have with the Q jet in this situation, it might be possible the power valve is opening slightly at idle. Won't be able to tell much more until the owner is able to work things out with the shop on payment and get the vehicle over for me to look at it further. We may order a Q jet master jetting kit that hopefully has the required parts to recalibrate the power valve and get the main circuits flowing right under load. |
'69 Olds 442 Idle Problem
On Aug 27, 12:25*pm, XR650L_Dave wrote:
On Aug 27, wrote: Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. *Towed the car to my home garage a block away. *Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). *The distributor bearings were also in dire shape so the dist was replaced. *It started and ran well now, but idled poorly. *I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. *Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. *Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. * *Everything else looked okay. *The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. *The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. *The engine had 250K plus miles. *He asked me if I wanted to do it, but I d too many irons in the fire. *So he took it to a decent local garage where they yanked the engine for a total rebuild. *Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. *Well, here is where it gets weird. * It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. *So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. *The cam timing and *ignition timing are checked and rechecked. *Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. *Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. *No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). *The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. *I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. *On many manifolds this area is open anyway. *I could TIG it up, but I guessing this would be a waste of time. *None of the carbs tried may have been jetted right for this engine. *Any Quadrajet/Olds experts out there care to weigh in? Stock carb, and the carbs they tried, could all have worn throttle shaft bushings. It's easy to overlook this vacuum leak, and it also allows the throttle plates to randomly open-and-close a bit as it idles. A Qjet in good shape is a *great* carb. Dave The shafts in the Q Jet carb that I last saw on the car are in good shape. |
'69 Olds 442 Idle Problem
On Aug 27, 3:16*pm, RBnDFW wrote:
Steve Lusardi wrote: The key is low idle vacuum. You have a leak or you have lost index on the balancer and TDC *needs to be verified. Don't overlook the brake vacuum booster, throttle shafts on the carb,PVC valve or EGR valve leakage. Steve No EGR on that one, though the aluminum manifold may have provision for one. "oldjag" wrote in message .... Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. *Towed the car to my home garage a block away. *Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). *The distributor bearings were also in dire shape so the dist was replaced. *It started and ran well now, but idled poorly. *I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. *Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. *Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. * *Everything else looked okay. *The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. *The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. *The engine had 250K plus miles. *He asked me if I wanted to do it, but I d too many irons in the fire. *So he took it to a decent local garage where they yanked the engine for a total rebuild. *Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. *Well, here is where it gets weird. *It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. *So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. *The cam timing and *ignition timing are checked and rechecked. *Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. *Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. *No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). *The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. *I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. *On many manifolds this area is open anyway. *I could TIG it up, but I guessing this would be a waste of time. *None of the carbs tried may have been jetted right for this engine. *Any Quadrajet/Olds experts out there care to weigh in? No EGR valve is in place. All vac lines were pulled off, and PCV checked and replaced with new. Damper was checked vs TDC when engine was apart and was supposedly okay. |
'69 Olds 442 Idle Problem
On Aug 27, 12:09*pm, Erik wrote:
In article , wrote: Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. *Towed the car to my home garage a block away. *Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). *The distributor bearings were also in dire shape so the dist was replaced. *It started and ran well now, but idled poorly. *I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. *Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. *Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. * *Everything else looked okay. *The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. *The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. *The engine had 250K plus miles. *He asked me if I wanted to do it, but I d too many irons in the fire. *So he took it to a decent local garage where they yanked the engine for a total rebuild. *Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. *Well, here is where it gets weird. * It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. *So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. *The cam timing and *ignition timing are checked and rechecked. *Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. *Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. *No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). *The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. *I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. *On many manifolds this area is open anyway. *I could TIG it up, but I guessing this would be a waste of time. *None of the carbs tried may have been jetted right for this engine. *Any Quadrajet/Olds experts out there care to weigh in? Hmmm... just for snorts & giggles, take a look at the harmonic balancer. Has deteriorating rubber allowed the outer ring (along with the timing mark) to slip around? Your low manifold vacuum that improves with advanced ignition timing is what makes me suspicious. Slipped balancers are not unheard of, especially on older engines. If this should be the case, there are places around that rebuild them for a lot less than new, ask the folks at your machine shop. Good luck, let us know how it comes out. Erik The damper was checked vs actual TDC when the engine was apart, and was okay as per the engine builder, but when I get my hands on the car it will be rechecked. |
'69 Olds 442 Idle Problem
On Aug 27, 8:29*pm, wrote:
On Thu, 27 Aug 2009 19:59:24 -0700, "Steve Lusardi" wrote: The key is low idle vacuum. You have a leak or you have lost index on the balancer and TDC *needs to be verified. Don't overlook the brake vacuum booster, throttle shafts on the carb,PVC valve or EGR valve leakage. Steve Don't overlook the vacuum break for the automatic choke either. VERY common failure point on '60s QJ carbs. *If the diaphragm is leaking you will NOT get it to idle smoothly. PERIOD. First thing I would do is verify compression. A good leakdown (aircraft type) tester *would be handy as well. *Then VERIFY ignition timing mark (damper) - and if compression is even but low verify valve timing. A good ignition scope and someone who knows how to read it can verify both primary and secondary ignition - I'd put a NEW set of the proper AC plugs in. With a hot cam, the proper plug will be COLDER than original. Then check or replace the wires and coil. My preference would be to put in a later model high energy (electronic) distributor with the coil built in. and 8mm mag-core wires Then check ALL vacuum devices for leaks. Block the lines to the heater controls for testing purposes, and use a "mighty-vac" to check all diapragms etc. Feed a bit of propane through a hose to all suspected vac leak areas (throttle shafts, base gaskets, etc that cannot be verified mechanically.. Unless the replacement cam is "wild" getting it to idle should not be hard. Getting it to PERFORM can be more difficult. "oldjag" wrote in ... Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. *Towed the car to my home garage a block away. *Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). *The distributor bearings were also in dire shape so the dist was replaced. *It started and ran well now, but idled poorly. *I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. *Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. *Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. * *Everything else looked okay. *The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. *The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. *The engine had 250K plus miles. *He asked me if I wanted to do it, but I d too many irons in the fire. *So he took it to a decent local garage where they yanked the engine for a total rebuild. *Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. *Well, here is where it gets weird. *It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. *So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. *The cam timing and *ignition timing are checked and rechecked. *Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. *Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. *No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). *The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. *I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. *On many manifolds this area is open anyway. *I could TIG it up, but I guessing this would be a waste of time. *None of the carbs tried may have been jetted right for this engine. *Any Quadrajet/Olds experts out there care to weigh in? Still waiting for the owner to get the car out of the shop where it is now, but the vac pull off is really something to be looked at. Plugs and wires are new, and a HEI dist. was installed, all vac lines were isolated, and propane checked were done, but as I noted that was done prior to the rebuild, so I'll probably need to go over a lot of things again. |
'69 Olds 442 Idle Problem
On Aug 28, 8:07*am, Larry Jaques
wrote: On Thu, 27 Aug 2009 20:59:09 -0700, the infamous JR North scrawled the following: Kudus for all the good replies. Huh? *Y'mean "kudos", Jace? *vbghttp://www.wildlife-pictures-online....u_slwp-0010_bl... I vote for 2 problems: 1. Problem started after 1st ditributor replacement: Timing is off. Going through several mechanics-must be basic, thus unfound. Verify TDC #1-ck balancer This is one I'd never seen while wrenching, but I have heard of it happening. 2. Vacuum leak-definately. Big one, too. I vote for brake booster. HVAC -not enough to materially affect idle. Intake manifolds replaced; unlikely but possible leaks bottom side of intake runners at head ports. PCV valve wide open-probable. Yeah, vacuum leaks are #2 for rough or no idle after clogged idle jet circuits (in unrebuildable Holleys. ;) *I didn't see many open brake boosters but saw lots of loose or split vacuum hoses, missing caps, misrouted vacuum lines, and open EGR valves in later models. I'd vote for the leak at the new Edelbrock intake. I saw that a whole lot. BTW: aint noth'n wrong with Qjets. Yeah, I much preferred Rottenchesters to Holleys for GM products. -- A striking fact of the last two years of financial trouble is how accountability has differed in the public and private spheres. On Wall Street and across the country, decades-old firms have failed, fortunes have vanished, and some former captains of finance face jail or fines. In Washington, meanwhile, most regulators and Members of Congress remain on the job, often with enhanced power. *-WSJ "Bernanke's Second Chance" 26aug09 Well, the owner is having the shop put the stock intake back on, as he does not want to pay for the Edlebrock or have a non-stock looking intake. |
'69 Olds 442 Idle Problem
On Aug 28, 11:28*am, RBnDFW wrote:
JR North wrote: 2. Vacuum leak-definately. Big one, too. I vote for brake booster. HVAC -not enough to materially affect idle. Intake manifolds replaced; unlikely but possible leaks bottom side of intake runners at head ports. When the heads were rebuilt, did they surface them? A deep cut or several light cuts can leave the manifold mismatched to the vee formed by the heads. If you end up pulling the manifold, check for port matching. Look at the gaskets you remove and try to determine if they were sealing all around each port. The heads were pretty straight, so only a few thou was removed. The shop working on it seems to think the intake gaskets were sealing to the heads, uniform pattern.etc., but who knows, until I see it again first hand I won't really know. |
'69 Olds 442 Idle Problem
On Aug 28, 5:21*pm, wrote:
On Wed, 26 Aug 2009 22:58:49 -0700 (PDT),oldjag wrote: Some metal content, (barely)...This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. *Towed the car to my home garage a block away. *Found very weak spark and traced problem to a made in China, Blue Steak brand distributor cap that was molded in such a way that the cap pushed on the breaker points, (actually Blue Streak quality was also bad years ago before they were made in China). *The distributor bearings were also in dire shape so the dist was replaced. *It started and ran well now, but idled poorly. *I checked the air/fuel ratio with a Innovate wide ratio afr meter and it was lean at idle, about 15-16 afr, and far too lean for an old car at idle. The owner had another Quadrajet carb., actually the one that came on the car, so I rebuilt it, installed a new fuel filter and reinstalled the carb. Other than the usual stripped inlet filter thread, the carb looked in good shape. On startup the air fuel was now okay, around 13:1 at idle, and the idle quality was better but still almost sounding like a miss when listening at the the tailpipes. I checked for air leaks, brake booster booster, PCV etc. *Ran a propane check to look for leaks around the manifold, compression was 200 psi. on six cylinders and 180-190 on two others. *Idle vacuum was kinda low at 14 inches, at the intial timing of 8 degrees. * *Everything else looked okay. *The car ran great except at idle, ie it pulled really well at WOT, chirped the tires when the automatic hit second gear etc., and lots of torque, but still a lousy idle. *The owner was satisfied for a while, but in the fall decided a engine rebuild was in order. *The engine had 250K plus miles. *He asked me if I wanted to do it, but I d too many irons in the fire. *So he took it to a decent local garage where they yanked the engine for a total rebuild. *Two valves appeared to have been leaking, so intially this was thought probable cause for the poor idle. *Well, here is where it gets weird. *It went off too the machine shop, got hot tanked, got a rebore 0.030" over, stock compression pistons, a 5 angle valve job, new valve, and valve springs, lifters, cam and main bearings, reground crank, fuel pump, oil pump, roller timing chain and gears, a new Pro Comp "mild cam" and a new non points type HEI distributor and wires. Now get this...it still does not idle right, in fact it's worse and power is down a quite a bit also. *So the garage tries two other (used) stock Quadrjet and two Holley carbs, still no dice. *The cam timing and *ignition timing are checked and rechecked. *Compression is now 220 psi on all eight. The CompCam is pulled, and an Edlebrock Performer Plus Cam installed. This is a pretty mild cam, almost stock duration, slightly more lift. Idle is still crap and vac. won't go over 12 inches unless the timing is advanced way up. *Next the garage pulls the stock intake manifold and puts on a Edlebrock Performer Plus aluminum intake. *No real change. (A hairline crack was noticed between the secondary bores of the stock iron intake, but this does not cause an external air leak and would not effect idle in any case). *The exhaust is then dropped and idle quality does not improve, ie still poor idle vac. The torque converter is unbolted from the flexplate, idle is still bad, vac. comes up slightly. Belts are pulled from the fan so no accessories are running, still no change. Now the garage wants more money to go further and the owner is livid. I told the owner to get to an agreement with the shop on who owes what and bring the car over to let me look at it. My feeling at this point is that the engine is probably healthy from a mechanical standpoint, but that the existing Quadrajet Carb.may simply need to be properly set up for the new cam. The plan now is to put the stock intake back on and sell the Edlebrock manifold, as the owner wants a stock looking motor. *I don't think the hairline crack between the secondary bores on the iron stock intake matters one iota. *On many manifolds this area is open anyway. *I could TIG it up, but I guessing this would be a waste of time. *None of the carbs tried may have been jetted right for this engine. *Any Quadrajet/Olds experts out there care to weigh in? Transmission modulator? Nope, checked that. |
'69 Olds 442 Idle Problem
On Aug 30, 9:25*pm, "Phil Kangas" wrote:
"oldjag" wrote in message Some metal content, (barely)... * *This started last spring actually when I helped a driver in an '69 olds 442 convertable that died on the roadside. *Towed the car to my home garage a block away. Hey thereoldjag, there's a lot of guys waiting to hear what you came up with to fix this idle problem! Let us know, eih? please........phil I should have more of an update soon. The owner brought it over yesterday and I took it for a drive. First impression when I first heard it is that it has a lot more cam duration in it than what was thought. It idles fairly lumpy at what sounds like about 850 RPM in neutral and gets worse in gear, but does not sound like a miss. It's not loading up, and it pulls strongly from a stop. Feels quite a bit stronger than a stock '69 442 Auto should. Also knocks a fair amount on premium at high RPM, probably because they dialed in so much initial advance to make it idle smoother. When I get some time, this weekend maybe, I hope to see if we can tweak the Qjet for a little better idle by changing the power valve spring. Another question is that Old's used a 45 degree valve lifter angle on some early 400's and a 39 degree bank angle on later engines. It's possible there was a mixup and it has the wrong cam for the specific block. To my knowledge it's the original engine in the car so it should be a 39 degree block with the correct cam for a 39 degree block. This can cause a hell of an idle problem as one bank is advanced and the other retarded but the engine will still run okay at higher speed. |
| All times are GMT +1. The time now is 06:21 AM. |
Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004 - 2014 DIYbanter