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Jim Wilkins May 2nd 10 06:34 PM

Carb jet?
 
I bought an old Powermate 3KW generator with a Tecumseh OHH55 5.5HP
engine that doesn't run as smoothly as I'd like, to me it sounds,
smells and the plug looks lean. The Date of Manufacture is 8068 which
appears to mean the 68th day of 1998, before gas contained 10%
ethanol. The carb looks like a Series 8, with no idle screw. The fixed
main jet is stamped 166.

Has anyone modified one of these to run better on modern gas? On other
old engines I back out the idle mixture screw, but this one doesn't
have one.

tia
jsw




[email protected] May 2nd 10 07:25 PM

Carb jet?
 
On Sun, 2 May 2010 10:34:59 -0700 (PDT), Jim Wilkins
wrote:

I bought an old Powermate 3KW generator with a Tecumseh OHH55 5.5HP
engine that doesn't run as smoothly as I'd like, to me it sounds,
smells and the plug looks lean. The Date of Manufacture is 8068 which
appears to mean the 68th day of 1998, before gas contained 10%
ethanol. The carb looks like a Series 8, with no idle screw. The fixed
main jet is stamped 166.

Has anyone modified one of these to run better on modern gas? On other
old engines I back out the idle mixture screw, but this one doesn't
have one.

tia
jsw


Could try a larger main jet? Or find a carb with an adjustable jet.
Generally it's the newer crap that is not adjustable (for emissions
control reasons)

Stormin Mormon May 2nd 10 07:40 PM

Carb jet?
 
I've worked on a couple Tec engines, with simple float
carbs. The metering is performed through the bolt that holds
the float bowl on. If you pull that bolt out, there is a
small hole in the side, that comes up through the center of
the bolt. Enlarging this hole will rich the mixture.

Before I did that (not reversible action) I'd want to try
fresh gas of good brand, air cleaner, new spark plug, take
the float bowl off and see if there's water, check the gap
from the flywheel to the coil, and all that good stuff.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Jim Wilkins" wrote in message
...
I bought an old Powermate 3KW generator with a Tecumseh
OHH55 5.5HP
engine that doesn't run as smoothly as I'd like, to me it
sounds,
smells and the plug looks lean. The Date of Manufacture is
8068 which
appears to mean the 68th day of 1998, before gas contained
10%
ethanol. The carb looks like a Series 8, with no idle screw.
The fixed
main jet is stamped 166.

Has anyone modified one of these to run better on modern
gas? On other
old engines I back out the idle mixture screw, but this one
doesn't
have one.

tia
jsw





John Husvar May 2nd 10 08:46 PM

New small engine Q. Was: Carb jet?
 
At work we have a Sears mower, about 5 years old. It has a Tecumseh
engine. On first attempt at using this Spring, it started backfiring
through the carb and will nearly break your arm when it pulls the start
handle out of your hand.

We found the flywheel key broken and replaced it with the correct Sears
Part Number. It still does the same thing, though not quite as bad.

Magnet to coil clearance is .003. Compression seems good.

Anybody have any ideas? (Well, other than changing the mechanism under
the nameplate or the nameplate above the mechanism, or both)

Lloyd E. Sponenburgh[_3_] May 2nd 10 09:01 PM

New small engine Q. Was: Carb jet?
 
John Husvar fired this volley in news:jhusvar-
:

We found the flywheel key broken and replaced it with the correct Sears
Part Number. It still does the same thing, though not quite as bad.


I'll venture a left-field guess.

I restored a Cushman motor scooter that had the same problem. The
ultimate problem was points timing. They were way too open (worn), so
they opened early enough to advance the timing too far.

But the intermediate problem was that every time I put a new key in the
flywheel, it immediately "half-sheared" it (before it fully sheared it),
so that the flywheel timing was off, too. That exacerbated the problem.

I guess if yours has fully-electronic ignition, this might not be the
problem.

LLoyd


[email protected] May 2nd 10 09:24 PM

Carb jet?
 
On Sun, 2 May 2010 14:40:43 -0400, "Stormin Mormon"
wrote:

I've worked on a couple Tec engines, with simple float
carbs. The metering is performed through the bolt that holds
the float bowl on. If you pull that bolt out, there is a
small hole in the side, that comes up through the center of
the bolt. Enlarging this hole will rich the mixture.

Before I did that (not reversible action) I'd want to try
fresh gas of good brand, air cleaner, new spark plug, take
the float bowl off and see if there's water, check the gap
from the flywheel to the coil, and all that good stuff.

There is also a replacement available for that bolt that has an
adjustable needle valve in it.

[email protected] May 2nd 10 09:26 PM

New small engine Q. Was: Carb jet?
 
On Sun, 02 May 2010 15:01:26 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

John Husvar fired this volley in news:jhusvar-
:

We found the flywheel key broken and replaced it with the correct Sears
Part Number. It still does the same thing, though not quite as bad.


I'll venture a left-field guess.

I restored a Cushman motor scooter that had the same problem. The
ultimate problem was points timing. They were way too open (worn), so
they opened early enough to advance the timing too far.

But the intermediate problem was that every time I put a new key in the
flywheel, it immediately "half-sheared" it (before it fully sheared it),
so that the flywheel timing was off, too. That exacerbated the problem.

I guess if yours has fully-electronic ignition, this might not be the
problem.

LLoyd

Sometimes being too lean on start will cause the kick-back too. And
the kickback CAN shear the timing key. Using a bit of medium lock-tite
on the crank taper can prevent the key from shearing too!!!

Jim Wilkins May 2nd 10 10:14 PM

Carb jet?
 
On May 2, 4:24*pm, wrote:
On Sun, 2 May 2010 14:40:43 -0400, "Stormin Mormon"

wrote:
I've worked on a couple Tec engines, with simple float
carbs. The metering is performed through the bolt that holds
the float bowl on. If you pull that bolt out, there is a
small hole in the side, that comes up through the center of
the bolt. Enlarging this hole will rich the mixture.


Before I did that (not reversible action) I'd want to try
fresh gas of good brand, air cleaner, new spark plug, take
the float bowl off and see if there's water, check the gap
from the flywheel to the coil, and all that good stuff.


*There is also a replacement available for that bolt that has an
adjustable needle valve in it.


Thanks. That bolt with 166 stamped on it is the main jet. I was hoping
there might be an ethanol replacement with a larger fixed orifice. No
luck so far searching on the net.

jsw

Bob Engelhardt May 2nd 10 11:02 PM

New small engine Q. Was: Carb jet?
 
wrote:

... Using a bit of medium lock-tite
on the crank taper can prevent the key from shearing too!!!


Uh ... the key is SUPPOSED to shear. Like when the mower hits a rock.
That's why they're made with aluminum. At least it's so for B&S engines.

Bob

[email protected] May 3rd 10 12:11 AM

New small engine Q. Was: Carb jet?
 
On Sun, 02 May 2010 18:02:50 -0400, Bob Engelhardt
wrote:

wrote:

... Using a bit of medium lock-tite
on the crank taper can prevent the key from shearing too!!!


Uh ... the key is SUPPOSED to shear. Like when the mower hits a rock.
That's why they're made with aluminum. At least it's so for B&S engines.

Bob

I'm aware of that. But getting an engine to START without shearing
the key is sometimes an issue.

The blade is on the OTHER end, and it also has a shear protection
device.
Using a bit of loctite can sometimes make the key last long enough to
find out what ELSE is wrong, to get the motor running.
I've been known to use a steel key for troubleshooting. A real good
idea to put the original back in after the problem is found and fixed,
but I've left a steel key in, or used lock-tite on a couple "cranky"
older engines.

Stormin Mormon May 3rd 10 01:44 AM

New small engine Q. Was: Carb jet?
 
See if the blade is loose. It needs the weight of the blade
to push the piston through the TDC.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"John Husvar" wrote in message
...
At work we have a Sears mower, about 5 years old. It has a
Tecumseh
engine. On first attempt at using this Spring, it started
backfiring
through the carb and will nearly break your arm when it
pulls the start
handle out of your hand.

We found the flywheel key broken and replaced it with the
correct Sears
Part Number. It still does the same thing, though not quite
as bad.

Magnet to coil clearance is .003. Compression seems good.

Anybody have any ideas? (Well, other than changing the
mechanism under
the nameplate or the nameplate above the mechanism, or both)



Stormin Mormon May 3rd 10 01:46 AM

New small engine Q. Was: Carb jet?
 
Sure. And then when you run over a rock or survey stake, the
machine will bend the crankshaft instead of shearing the
flywheel key. F'ing brilliant, you think?

Hint for Clare only: Some devices have a reason for
existance.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


wrote in message
...

Sometimes being too lean on start will cause the kick-back
too. And
the kickback CAN shear the timing key. Using a bit of medium
lock-tite
on the crank taper can prevent the key from shearing too!!!



Stormin Mormon May 3rd 10 01:47 AM

New small engine Q. Was: Carb jet?
 
I've never seen a shear protection device on a lawn mower
blade. God help you.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


wrote in message
...


The blade is on the OTHER end, and it also has a shear
protection
device.




Greg O[_2_] May 3rd 10 03:43 AM

New small engine Q. Was: Carb jet?
 

wrote in message
...
device.

Using a bit of loctite can sometimes make the key last long enough to
find out what ELSE is wrong, to get the motor running.
I've been known to use a steel key for troubleshooting. A real good
idea to put the original back in after the problem is found and fixed,
but I've left a steel key in, or used lock-tite on a couple "cranky"
older engines.


If you are having problems with the aluminum flywheel key shearing when
starting the engine you have either a bad fit on the flywheel taper, or not
enough torque on the flywheel nut.
I have run Briggs engines without a flywheel key, the taper will hold the
flywheel in place, the key is just to locate the flywheel for timing.
Greg


Gunner Asch[_6_] May 3rd 10 03:55 AM

New small engine Q. Was: Carb jet?
 
On Sun, 2 May 2010 20:47:55 -0400, "Stormin Mormon"
wrote:

I've never seen a shear protection device on a lawn mower
blade. God help you.



Actually...neither have I. Nor have I seen a bent crank in any decent
quality lawn mower motor.

And here in the desert..running over rocks, sprinkler heads and whatnot
is pretty common


Gunner

--

"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost

Bill Noble[_2_] May 3rd 10 04:54 AM

Carb jet?
 
raise the float level a little

"Jim Wilkins" wrote in message
...
I bought an old Powermate 3KW generator with a Tecumseh OHH55 5.5HP
engine that doesn't run as smoothly as I'd like, to me it sounds,
smells and the plug looks lean. The Date of Manufacture is 8068 which
appears to mean the 68th day of 1998, before gas contained 10%
ethanol. The carb looks like a Series 8, with no idle screw. The fixed
main jet is stamped 166.

Has anyone modified one of these to run better on modern gas? On other
old engines I back out the idle mixture screw, but this one doesn't
have one.

tia
jsw




[email protected] May 3rd 10 04:57 AM

New small engine Q. Was: Carb jet?
 
On Sun, 2 May 2010 20:47:55 -0400, "Stormin Mormon"
wrote:

I've never seen a shear protection device on a lawn mower
blade. God help you.

Well, mine BOTH have what look like soft solid rivets through the
blade and the hub. Actually - only the one I now have plus the one I
just got rid of last year. My "other" current one has a belt drive
blade which provides SOME protection - not to the blade and spindle,
but lots to the motor.

Virtually all Lawn Boy mowers have the sheer protectors, as well.

See part# 410-910 on
http://www.bantasaw.com/catalog/pdf/...ccessories.pdf

A lot of the cheap crap doesn't have any blade shear protection
because it's cheaper to replace the whole mower than it is to sharpen
a blade. (well, allmost - you know what I mean)

[email protected] May 3rd 10 05:04 AM

New small engine Q. Was: Carb jet?
 
On Sun, 2 May 2010 20:46:54 -0400, "Stormin Mormon"
wrote:

Sure. And then when you run over a rock or survey stake, the
machine will bend the crankshaft instead of shearing the
flywheel key. F'ing brilliant, you think?

Hint for Clare only: Some devices have a reason for
existance.

The shear pin on the TOP of the engine gives minimal protection to
the shaft on the BOTTOM of the engine. By shearing at the flywheel end
it shuts the engine off immediately upon hitting something - limiting
the amount of damage it will do to the crank - but certainly not
eliminating damage.

And did you also know that trying to start the average vertical shaft
lawn mower engine without a blade attached CAN shear the flywheel
key?? This is because the "flywheel" on most current vertical shaft
engines designed for direct blade attachment is way too light to allow
the engine to run without the blade and the torsional reversals are
strong enough to shear the key. The BLADE is the actual "flywheel"
that provides the required inertia on these engines.
Older engines with cast iron flywheels and horizontal shaft engines do
not have this issue.

Gerald Miller May 3rd 10 06:13 AM

New small engine Q. Was: Carb jet?
 
On Sun, 02 May 2010 19:55:30 -0700, Gunner Asch
wrote:

On Sun, 2 May 2010 20:47:55 -0400, "Stormin Mormon"
wrote:

I've never seen a shear protection device on a lawn mower
blade. God help you.


I have had a couple cheap mowers that the blades were driven by steel
rivets with the head in a dimple in the drive hub

Actually...neither have I. Nor have I seen a bent crank in any decent
quality lawn mower motor.

Last fall Junior dragged a rear bagger home and I used to pick up all
the 20+ bags of leaves after I got the run out down from 0.1 to less
than 0.01" by judicious repeated application of a 4 pound hammer

And here in the desert..running over rocks, sprinkler heads and whatnot
is pretty common


Gunner

--

"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost

Gerry :-)}
London, Canada

pyotr filipivich May 3rd 10 06:34 AM

New small engine Q. Was: Carb jet?
 
Gerald Miller on Mon, 03 May 2010 01:13:49 -0400
typed in rec.crafts.metalworking the following:
On Sun, 02 May 2010 19:55:30 -0700, Gunner Asch
wrote:

On Sun, 2 May 2010 20:47:55 -0400, "Stormin Mormon"
wrote:

I've never seen a shear protection device on a lawn mower
blade. God help you.


I have had a couple cheap mowers that the blades were driven by steel
rivets with the head in a dimple in the drive hub

Actually...neither have I. Nor have I seen a bent crank in any decent
quality lawn mower motor.

Last fall Junior dragged a rear bagger home and I used to pick up all
the 20+ bags of leaves after I got the run out down from 0.1 to less
than 0.01" by judicious repeated application of a 4 pound hammer


Precision work requires the right tool for the job. You couldn't
do that with a bigger hammer.
-
pyotr filipivich
We will drink no whiskey before its nine.
It's eight fifty eight. Close enough!

Bob Engelhardt May 3rd 10 06:37 PM

New small engine Q. Was: Carb jet?
 
wrote:
The shear pin on the TOP of the engine gives minimal protection to
the shaft on the BOTTOM of the engine. By shearing at the flywheel end
it shuts the engine off immediately upon hitting something - limiting
the amount of damage it will do to the crank - but certainly not
eliminating damage.

[snip]

I think that's right. Except the crank is already garbage & shutting
off is probably to prevent collateral damage. And to keep the
operator's underwear clean G.

Bob


Bob Engelhardt May 3rd 10 06:42 PM

New small engine Q. Was: Carb jet?
 
Gunner Asch wrote:
... Nor have I seen a bent crank in any decent
quality lawn mower motor.


Oh, I have. One day at the dump a lady brought in a nearly-new Honda or
Toro. I blindsided a couple of other scroungers to get to it first,
only to find a bent shaft. I was tempted to try to straighten it, just
for the experience & satisfaction, but common sense prevailed.

Bob

Gunner Asch[_6_] May 3rd 10 07:42 PM

New small engine Q. Was: Carb jet?
 
On Mon, 03 May 2010 13:42:20 -0400, Bob Engelhardt
wrote:

Gunner Asch wrote:
... Nor have I seen a bent crank in any decent
quality lawn mower motor.


Oh, I have. One day at the dump a lady brought in a nearly-new Honda or
Toro. I blindsided a couple of other scroungers to get to it first,
only to find a bent shaft. I was tempted to try to straighten it, just
for the experience & satisfaction, but common sense prevailed.

Bob



That would have been an interesting project though..if one had the time
and the tools to bend it. Course, doesnt take much tooling...decent
hydraulic press, good indicator...shrug

Buddy of mine straightened the only bent one Id ever seen, using a pair
of borrowed V blocks and a big! brass hammer I have kicking around here.
I put a piece of blanchard ground plate on one of my surface plates and
turned him loose. Far as I know..he is still running the mower some 4-5
yrs later.

Gunner

--


"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost

Greg O[_2_] May 4th 10 03:31 AM

New small engine Q. Was: Carb jet?
 

wrote in message
...
On Sun, 2 May 2010 20:47:55 -0400, "Stormin Mormon"
wrote:

I've never seen a shear protection device on a lawn mower
blade. God help you.

Well, mine BOTH have what look like soft solid rivets through the
blade and the hub. Actually - only the one I now have plus the one I
just got rid of last year. My "other" current one has a belt drive
blade which provides SOME protection - not to the blade and spindle,
but lots to the motor.

Virtually all Lawn Boy mowers have the sheer protectors, as well.

See part# 410-910 on
http://www.bantasaw.com/catalog/pdf/...ccessories.pdf

A lot of the cheap crap doesn't have any blade shear protection
because it's cheaper to replace the whole mower than it is to sharpen
a blade. (well, allmost - you know what I mean)


I would like to know what mower that fits. I ran a small engine shop for a
few years and worked on a ton of Lawn Boys, models dating all the way back
to the late 50's and I have not seen anything but the tapered blade adaptor
that LB used for decades.
Greg


Gerald Miller May 4th 10 05:58 AM

New small engine Q. Was: Carb jet?
 
On Mon, 3 May 2010 21:31:58 -0500, "Greg O"
wrote:


wrote in message
.. .
On Sun, 2 May 2010 20:47:55 -0400, "Stormin Mormon"
wrote:

I've never seen a shear protection device on a lawn mower
blade. God help you.

Well, mine BOTH have what look like soft solid rivets through the
blade and the hub. Actually - only the one I now have plus the one I
just got rid of last year. My "other" current one has a belt drive
blade which provides SOME protection - not to the blade and spindle,
but lots to the motor.

Virtually all Lawn Boy mowers have the sheer protectors, as well.

See part# 410-910 on
http://www.bantasaw.com/catalog/pdf/...ccessories.pdf

A lot of the cheap crap doesn't have any blade shear protection
because it's cheaper to replace the whole mower than it is to sharpen
a blade. (well, allmost - you know what I mean)


I would like to know what mower that fits. I ran a small engine shop for a
few years and worked on a ton of Lawn Boys, models dating all the way back
to the late 50's and I have not seen anything but the tapered blade adaptor
that LB used for decades.
Greg

I have an old brown Lawn Boy out in the shed but don't recall what the
blade drive was like, perhaps if I find time tomorrow.......
Gerry :-)}
London, Canada

[email protected] May 4th 10 06:22 PM

New small engine Q. Was: Carb jet?
 
On Mon, 3 May 2010 21:31:58 -0500, "Greg O"
wrote:


wrote in message
.. .
On Sun, 2 May 2010 20:47:55 -0400, "Stormin Mormon"
wrote:

I've never seen a shear protection device on a lawn mower
blade. God help you.

Well, mine BOTH have what look like soft solid rivets through the
blade and the hub. Actually - only the one I now have plus the one I
just got rid of last year. My "other" current one has a belt drive
blade which provides SOME protection - not to the blade and spindle,
but lots to the motor.

Virtually all Lawn Boy mowers have the sheer protectors, as well.

See part# 410-910 on
http://www.bantasaw.com/catalog/pdf/...ccessories.pdf

A lot of the cheap crap doesn't have any blade shear protection
because it's cheaper to replace the whole mower than it is to sharpen
a blade. (well, allmost - you know what I mean)


I would like to know what mower that fits. I ran a small engine shop for a
few years and worked on a ton of Lawn Boys, models dating all the way back
to the late 50's and I have not seen anything but the tapered blade adaptor
that LB used for decades.
Greg

They ARE tapered shaft adapters - any (well - MANY, anyways - of the
"square plate" type steel blade adapters use the shear rivets. Some
of the die-cast adapters also used the shear rivets.
Look for DOP65-200LB on
http://www.discountonlineparts.com/l...ade%20Adapters



Greg O[_2_] May 5th 10 04:46 AM

New small engine Q. Was: Carb jet?
 

wrote in message
...
They ARE tapered shaft adapters - any (well - MANY, anyways - of the

"square plate" type steel blade adapters use the shear rivets. Some
of the die-cast adapters also used the shear rivets.
Look for DOP65-200LB on
http://www.discountonlineparts.com/l...ade%20Adapters



That is the one I remember seeing, but never saw any rivits in any of them.
There are two punched holes that are raised to drive the blade.
Greg


Jim Wilkins May 5th 10 06:03 PM

Carb jet?
 
On May 2, 5:14*pm, Jim Wilkins wrote:
...
...That bolt with 166 stamped on it is the main jet. I was hoping
there might be an ethanol replacement with a larger fixed orifice. No
luck so far searching on the net.
jsw-


The small engine shop gave me a used, larger 163 jet to try. (should
prefix it "Me-") It passes an 0.036" drill bit which the 166 doesn't.
So far the engine runs smoother but the plug still reads lean.

Wouldn't you expect a universal problem like this to have a simple,
well-publicized solution? I've had to retune all my small engines for
gas with ethanol.

jsw

[email protected] May 6th 10 12:00 AM

New small engine Q. Was: Carb jet?
 
On Tue, 4 May 2010 22:46:01 -0500, "Greg O"
wrote:


wrote in message
.. .
They ARE tapered shaft adapters - any (well - MANY, anyways - of the

"square plate" type steel blade adapters use the shear rivets. Some
of the die-cast adapters also used the shear rivets.
Look for DOP65-200LB on
http://www.discountonlineparts.com/l...ade%20Adapters



That is the one I remember seeing, but never saw any rivits in any of them.
There are two punched holes that are raised to drive the blade.
Greg

All 3 old lawnboys I used to look after are gone now so I can't get
the models - all 3 were green - 2 had magnesium decks, and all had
easy-spin starting (pull straight up with your fingers). Can't
remember if they were electronic or point ignition, but all 3 had
shear rivets. When the lower seals went bad and they got hard to start
all 3 got disposed of, one at a time, over a period of 3 years.
Neighbours all have 4 strokers now..

Lloyd E. Sponenburgh[_3_] May 6th 10 01:27 AM

New small engine Q. Was: Carb jet?
 
fired this volley in
:

2 had magnesium decks,


Not. They had "Elektron Alloy" decks. It's a Mg/Al alloy. FWIW, though,
they did CALL them "magnesium decks".

LLoyd


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