The gauge on my old compression tester decided it had served well enough after several years of non-use, it's demise helped along by a good dose of rust. I needed one for a project car I just started working on so I went ebay shopping for a replacement gauge to go on my hose & adapters.

I found a Proto CTR-20 gauge on ebay, USA made, brand new according to seller, with a release valve for a good price of $15 including shipping but there isn't a check valve to hold the pressure for cumulative readings. On my old gauge, it must be built into the gauge's body as I don't see any kind of external check valve on it.

When cranking the engine, the needle jumps up to max and back to zero for each cycle. I'm not familiar with how a standard automotive compression tester is supposed to work here, other than it should hold the pressure and increase the reading a bit with each crank cycle of the motor.

Can anyone enlighten me on how to get this working the way I remember it should?

Here's the gauge screwed onto my hose:
http://www.token.crwoodturner.com/im...iongauge01.jpg
http://www.token.crwoodturner.com/im...iongauge02.jpg

Ken Grunke wrote:
The gauge on my old compression tester decided it had served well enough after several
years of non-use, it's demise helped along by a good dose of rust. I needed one for a
project car I just started working on so I went ebay shopping for a replacement gauge
to go on my hose & adapters.

I found a Proto CTR-20 gauge on ebay, USA made, brand new according to seller, with a
release valve for a good price of $15 including shipping but there isn't a check valve
to hold the pressure for cumulative readings. On my old gauge, it must be built into
the gauge's body as I don't see any kind of external check valve on it.

When cranking the engine, the needle jumps up to max and back to zero for each cycle.
I'm not familiar with how a standard automotive compression tester is supposed to work
here, other than it should hold the pressure and increase the reading a bit with each
crank cycle of the motor.

Can anyone enlighten me on how to get this working the way I remember it should?

Here's the gauge screwed onto my hose:
http://www.token.crwoodturner.com/im...iongauge01.jpg
http://www.token.crwoodturner.com/im...iongauge02.jpg



Not how it's supposed to work. Most of them use a check valve in the plug adapter fitting
on the end of the hose. 99% use a tire valve core type valve. Looks just like the release
valve in that T fitting on the old gauge.

Oh the old unit uses nothing more than a bog standard air pressure gauge with a
"compression tester" face on it. The spark adapter fittings are the part that makes it
special.

--
Steve W.

"Steve W." wrote in message ...


tire valve core

"Schrader"

"Steve W." wrote in message
...

Oh the old unit uses nothing more than a bog standard air pressure
gauge with a "compression tester" face on it. The spark adapter
fittings are the part that makes it special.

Steve W.

If the check valve was further up the hose the dead space would lower
the reading.

On Tue, 19 Mar 2013 13:16:18 -0700 (PDT), Ken Grunke
wrote:

The gauge on my old compression tester decided it had served well enough after several years of non-use, it's demise helped along by a good dose of rust. I needed one for a project car I just started working on so I went ebay shopping for a replacement gauge to go on my hose & adapters.

I found a Proto CTR-20 gauge on ebay, USA made, brand new according to seller, with a release valve for a good price of $15 including shipping but there isn't a check valve to hold the pressure for cumulative readings. On my old gauge, it must be built into the gauge's body as I don't see any kind of external check valve on it.

When cranking the engine, the needle jumps up to max and back to zero for each cycle. I'm not familiar with how a standard automotive compression tester is supposed to work here, other than it should hold the pressure and increase the reading a bit with each crank cycle of the motor.

Can anyone enlighten me on how to get this working the way I remember it should?

Here's the gauge screwed onto my hose:
http://www.token.crwoodturner.com/im...iongauge01.jpg
http://www.token.crwoodturner.com/im...iongauge02.jpg

It jumps to 300 lbs on each crank and then drops off again?

The gauge is missing a check valve in the bottom of the hose above the
spark plug adapter


The methodology of the left has always been:

1. Lie
2. Repeat the lie as many times as possible
3. Have as many people repeat the lie as often as possible
4. Eventually, the uninformed believe the lie
5. The lie will then be made into some form oflaw
6. Then everyone must conform to the lie

On Mar 19, 1:16*pm, Ken Grunke wrote:
The gauge on my old compression tester decided it had served well enough after several years of non-use, it's demise helped along by a good dose of rust. I needed one for a project car I just started working on so I went ebay shopping for a replacement gauge to go on my hose & adapters.

I found a Proto CTR-20 gauge on ebay, USA made, brand new according to seller, with a release valve for a good price of $15 including shipping but there isn't a check valve to hold the pressure for cumulative readings. On my old gauge, it must be built into the gauge's body as I don't see any kind of external check valve on it.

When cranking the engine, the needle jumps up to max and back to zero for each cycle. I'm not familiar with how a standard automotive compression tester is supposed to work here, other than it should hold the pressure and increase the reading a bit with each crank cycle of the motor.

Can anyone enlighten me on how to get this working the way I remember it should?

Here's the gauge screwed onto my hose:http://www.token.crwoodturner.com/im...iongauge02.jpg

What's puzzling to me is why you purchased this gauge other than you
were looking to squeeze a penny as hard as possible. :)

Steve W. wrote:

Ken Grunke wrote:
The gauge on my old compression tester decided it had served well enough
after several years of non-use, it's demise helped along by a good dose
of rust. I needed one for a project car I just started working on so I
went ebay shopping for a replacement gauge to go on my hose & adapters.

I found a Proto CTR-20 gauge on ebay, USA made, brand new according to
seller, with a release valve for a good price of $15 including shipping
but there isn't a check valve to hold the pressure for cumulative
readings. On my old gauge, it must be built into the gauge's body as I
don't see any kind of external check valve on it.

When cranking the engine, the needle jumps up to max and back to zero for
each cycle. I'm not familiar with how a standard automotive compression
tester is supposed to work here, other than it should hold the pressure
and increase the reading a bit with each crank cycle of the motor.

Can anyone enlighten me on how to get this working the way I remember it
should?

Here's the gauge screwed onto my hose:
http://www.token.crwoodturner.com/im...iongauge01.jpg
http://www.token.crwoodturner.com/im...iongauge02.jpg



Not how it's supposed to work. Most of them use a check valve in the plug
adapter fitting on the end of the hose. 99% use a tire valve core type
valve. Looks just like the release valve in that T fitting on the old
gauge.

Oh the old unit uses nothing more than a bog standard air pressure gauge
with a "compression tester" face on it. The spark adapter fittings are the
part that makes it special.


Perhaps Ken can rescue the adapters with check valves off the old gauge. The
fittings are probably standard pipe thread with some Teflon tape.

My compression gauge has a two piece adapter. The adapter for larger spark
plug threads can be unscrewed for the smaller plug sizes. Once this part is
unscrewed, the tire valve type check valve is clearly visible and can be
removed/replaced with a (cheap) special tool.

--
Paul Hovnanian
------------------------------------------------------------------
2 + 2 = 5 for extremely large values of 2.

PrecisionmachinisT wrote:
"Steve W." wrote in message ...


tire valve core

"Schrader"

Yep, A Schrader type valve core. However some folks don't know that name.


--
Steve W.

Jim Wilkins wrote:
"Steve W." wrote in message
...
Oh the old unit uses nothing more than a bog standard air pressure
gauge with a "compression tester" face on it. The spark adapter
fittings are the part that makes it special.

Steve W.

If the check valve was further up the hose the dead space would lower
the reading.



I have units with the valve at the tip and one with the valve right at the gauge. No
difference in the readings but they ones at the adapters are easier to change out.

--
Steve W.

On Mar 19, 9:31*pm, "Steve W." wrote:
Jim Wilkins wrote:
"Steve W." wrote in message
...
Oh the old unit uses nothing more than a bog standard air pressure
gauge with a "compression tester" face on it. The spark adapter
fittings are the part that makes it special.

Steve W.

If the check valve was further up the hose the dead space would lower
the reading.

I have units with the valve at the tip and one with the valve right at the gauge. No
difference in the readings but they ones at the adapters are easier to change out.

--
Steve W.

I like the ones that have a quality rubber condom around the gauge.

How soon before we start taking about what we use to check TDC?

ugh this Google Group thing is scary, I'll get me a *real* newsgroup reader....

So I am missing the Schrader valve, I don't see it in the hose end where the adapters screw on to, nor in the fitting at the gauge. So it's either inside the gauge or it's just plain lost. I haven't used the thing for eons, it sat on a shelf in the garage but I do remember it working back in the day when I still had most of my hair and better eyesight. I did buy the thing new and used it a few times.

It jumps to 300 lbs on each crank and then drops off again?

No Gunner it goes up to whatever that cylinder's pressure is, the four cylinders varied between 150 and 200 on a 20 yr old engine.

The gauge is missing a check valve in the bottom of the hose above the
spark plug adapter

Bingo, I had everything apart and do not see any check valve or schrader valve.

What's puzzling to me is why you purchased this gauge other than you
were looking to squeeze a penny as hard as possible. :)

Sure I'm trying to save a couple bucks, and also trying to avoid the Chinese crap that is rampant on ebay (and everywhere else). I live in the boonies and don't hit the metropolis very often. And yes, I am a penny pincher on a limited income.

Perhaps Ken can rescue the adapters with check valves off the old gauge. The
fittings are probably standard pipe thread with some Teflon tape.

My compression gauge has a two piece adapter. The adapter for larger spark
plug threads can be unscrewed for the smaller plug sizes. Once this part is
unscrewed, the tire valve type check valve is clearly visible and can be
removed/replaced with a (cheap) special tool.

Paul, I am using the adapters and hose from my old tester with the new gauge in place of the rusty old one. Maybe at some point the check valve fell out when I was switching adapters? Dunno.

Guys, thanks for the replies, I'm gonna sleep on it and maybe look for another gauge on ebay in the morning. BTW the seller was a fabulous guy who offered a full refund including shipping. I searched high and low for the box the gauge came in and told him I couldnt find it, expecting him to refuse the refund. But he answered back don't even bother returning the unit, just use it for a paperweight and then he refunded the full amount. Now there's a nomination for ebay seller of the year

On Mar 19, 11:05*pm, Ken Grunke wrote:
ugh this Google Group thing is scary, I'll get me a *real* newsgroup reader...

So I am missing the Schrader valve, I don't see it in the hose end where the adapters screw on to, nor in the fitting at the gauge. *So it's either inside the gauge or it's just plain lost. I haven't used the thing for eons, it sat on a shelf in the garage but I do remember it working back in the day when I still had most of my hair and better eyesight. I did buy the thing new and used it a few times.

It jumps to 300 lbs on each crank and then drops off again?

No Gunner it goes up to whatever that cylinder's pressure is, the four cylinders varied between 150 and 200 on a 20 yr old engine.

The gauge is missing a check valve in the bottom of the hose above the
spark plug adapter

Bingo, I had everything apart and do not see any check valve or schrader valve.

What's puzzling to me is why you purchased this gauge other than you
were looking to squeeze a penny as hard as possible. :)

Sure I'm trying to save a couple bucks, and also trying to avoid the Chinese crap that is rampant on ebay (and everywhere else). I live in the boonies and don't hit the metropolis very often. And yes, I am a penny pincher on a limited income.

Perhaps Ken can rescue the adapters with check valves off the old gauge. The
fittings are probably standard pipe thread with some Teflon tape.

My compression gauge has a two piece adapter. The adapter for larger spark
plug threads can be unscrewed for the smaller plug sizes. Once this part is
unscrewed, the tire valve type check valve is clearly visible and can be
removed/replaced with a (cheap) special tool.

Paul, I am using the adapters and hose from my old tester with the new gauge in place of the rusty old one. *Maybe at some point the check valve fell out when I was switching adapters? Dunno.

Guys, thanks for the replies, I'm gonna sleep on it and maybe look for another gauge on ebay in the morning. BTW the seller was a fabulous guy who offered a full refund including shipping. I searched high and low for the box the gauge came in and told him I couldnt find it, expecting him to refuse the refund. But he answered back don't even bother returning the unit, just use it for a paperweight and then he refunded the full amount. Now there's a nomination for ebay seller of the year

"Sure I'm trying to save a couple bucks, and also trying to avoid the
Chinese crap that is rampant on ebay (and everywhere else). I live in
the boonies and don't hit the metropolis very often. And yes, I am a
penny pincher on a limited income."

New quality tools are almost never cheap.

http://www.matcotools.com/catalog/pr...N-TESTING-SET/

You might try putting some soapy water or spit around the fitting where the
release button is, just below the gage to see if bubbles are present with
some pressure applied.
Then, if that release button assembly can be disassembled, you might find a
fleck of dirt or possibly a missing ball or spring.

In the section where the button is, there should probably be a check valve
which holds the pressure in the gage until the user presses the button.

There are also some types of compression testers which have the check/tire
valve core located at the end of the tube where the rubber tip is (which is
intended to seal in the spark plug hole.

But the release button on the Proto gage should engage something acting as a
check valve.

Another less likely fault could be that there is an internal leak in the
Proto gage, which is a little more complicated to check and repair, but
possible.

--
WB
..........


"Ken Grunke" wrote in message
...
The gauge on my old compression tester decided it had served well enough
after several years of non-use, it's demise helped along by a good dose of
rust. I needed one for a project car I just started working on so I went
ebay shopping for a replacement gauge to go on my hose & adapters.

I found a Proto CTR-20 gauge on ebay, USA made, brand new according to
seller, with a release valve for a good price of $15 including shipping but
there isn't a check valve to hold the pressure for cumulative readings. On
my old gauge, it must be built into the gauge's body as I don't see any kind
of external check valve on it.

When cranking the engine, the needle jumps up to max and back to zero for
each cycle. I'm not familiar with how a standard automotive compression
tester is supposed to work here, other than it should hold the pressure and
increase the reading a bit with each crank cycle of the motor.

Can anyone enlighten me on how to get this working the way I remember it
should?

Here's the gauge screwed onto my hose:
http://www.token.crwoodturner.com/im...iongauge01.jpg
http://www.token.crwoodturner.com/im...iongauge02.jpg

Wild_Bill wrote:
In the section where the button is, there should probably be a check valve
which holds the pressure in the gage until the user presses the button.

Nope, it's just the release valve. That works fine. I can blow into the hose with all my cheekmuscles, and the button will release the pressure - there is nothing between the gauge and the plug adapter, only a free passage. Same with the old gauge, it has only the release valve. That one is a Schrader valve in a T-fitting just below the gauge which is plainly seen in my first pictu
http://www.token.crwoodturner.com/im...iongauge01.jpg

I am assuming there has to be a separate check valve INLINE between the plug adapter and the gauge below the release valve. That is what I am missing. It may be a fitting I had, but absent-mindedly misplaced.

"Steve W." wrote in message
...
PrecisionmachinisT wrote:
"Steve W." wrote in message
...


tire valve core

"Schrader"

Yep, A Schrader type valve core. However some folks don't know that name.


Well, they do now...

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:


"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.

--
Ed Huntress

On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:


"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.

Whup, I hit "send" too fast. The leak-down tester also has a Schrader
valve, for filling the cylinder with air.

Am I repeating stuff that's been said? If so, I apologize.

--
Ed Huntress

Ed Huntress wrote:
On Wed, 20 Mar 2013 21:56:51 -0400, wrote:

On Wed, 20 Mar 2013 21:38:05 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 18:24:12 -0700 (PDT), jon_banquer
wrote:

On Mar 20, 6:04 pm, Ed Huntress
wrote:
On Wed, 20 Mar 2013 19:59:49 -0400,
wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...



I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve.
That is what I am missing. It may be a fitting I had,
but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked
up at the spark plug fitting end...

--FWIW blowing into the end with your mouth probably
won't produce enough hose expansion to actuate a ball
type check valve.

Sorry for jumping into the middle without having read the
thread, but there are two kinds of compression testers:
the regular kind, which have a button to activate the
check-release valve; and leak-down testers, which have no
such valve.

I have both. They look almost the same. Perhaps, if Ken's
tester doesn't have a check valve, he has a leakdown
tester. If so, it will have a spark-plug-thread terminal
end. Regular testers *may* have such a thread. Mine just
has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a
connector for compressed air.

Mine has one gauge. It's around 45 years old. And as I noted
in an addition to the post above, it has a Schrader valve for
pumping up the cylinder.

What's the second gauge for? With mine, you just attach it,
make sure both valves are closed, and pump it up. Test dry,
then test wet (with about an ounce of oil in the cylinder;
more for a V-engine).

Is there something else that I've missed?

-- Ed Huntress

One gauge tells you your air input pressure, the other your
cylinder pressure.

I don't understand that. All you care about is the air you get
into the cylinder, right?

I used to do a lot of leakdown tests, and I think I remember how
they were done. All I did was pump the cylinder up to some
pressure and time how long it takes to drop to some lower
pressure. Do the test dry, then wet, in each cylinder. If it
falls faster when dry, it's rings. If it's the same time when
wet, it's valves.

Am I missing something?
I guess you can do it that way, but it's not terribly effective or
accurate. A normal leakdown tester feeds 80psi to one side of a
restriction, which feeds the air into the cyl. Guage on inlet
(generally 80 psi) and on the cyl side. With no leakage at all you
get 80/80. If you have a small leakdown (normal) you may have
80/75. A sognificant leak may give you 80/60 or 80/50.

Then you listen in the intake, exhaust, and crankcase to tell
where the air is going.

Yeah, I can see that it's very quick to diagnose several problems.
But watch out what you call "normal." g Unless I'm mistaken, those
two-gauge deals didn't exist when I was club racing, in the late
'60s and early '70s. At least, it wasn't equipment that we
bottom-dollar sports car types had. The ones we used were "normal"
then.

I do see a limitiation of this newer device, compared to the old
ones, however. I described it in one of my posts to Jon.



The leakdown testers were used in aviation. The calibrated leak in the
tester has a spec. for hole size and length as well as other
dimensions. There are more than one size of calibrated leak. For
larger cylinders such as a 200 Cu In on a 1820 Wright you had to use a
larger calibrated leak gauge or every reading would indicate a bad cylinder.

http://en.wikipedia.org/wiki/Leak-down_tester


John

On Wed, 20 Mar 2013 06:32:46 -0700 (PDT), Ken Grunke
wrote:

Wild_Bill wrote:
In the section where the button is, there should probably be a check valve
which holds the pressure in the gage until the user presses the button.

Nope, it's just the release valve. That works fine. I can blow into the hose with all my cheekmuscles, and the button will release the pressure - there is nothing between the gauge and the plug adapter, only a free passage. Same with the old gauge, it has only the release valve. That one is a Schrader valve in a T-fitting just below the gauge which is plainly seen in my first pictu
http://www.token.crwoodturner.com/im...iongauge01.jpg

I am assuming there has to be a separate check valve INLINE between the plug adapter and the gauge below the release valve. That is what I am missing. It may be a fitting I had, but absent-mindedly misplaced.

Yes, and they usually fit into the line as you assumed. My old
Snap-On has some at the air fitting end and some at the plug end.
Look for internal threads at both ends of your adapter, Ken.
The only thing which may be missing is a schrader valve insert.

--
In order to become the master, the politician poses as the servant.
--Charles de Gaulle

On Wed, 20 Mar 2013 06:32:46 -0700 (PDT), Ken Grunke
wrote:

Wild_Bill wrote:
In the section where the button is, there should probably be a check valve
which holds the pressure in the gage until the user presses the button.

Nope, it's just the release valve. That works fine. I can blow into the hose with all my cheekmuscles, and the button will release the pressure - there is nothing between the gauge and the plug adapter, only a free passage. Same with the old gauge, it has only the release valve. That one is a Schrader valve in a T-fitting just below the gauge which is plainly seen in my first pictu
http://www.token.crwoodturner.com/im...iongauge01.jpg

I am assuming there has to be a separate check valve INLINE between the plug adapter and the gauge below the release valve. That is what I am missing. It may be a fitting I had, but absent-mindedly misplaced.
Is there an internal thread anywhere in the end of the hose/fitting?
If so, pop a tire valve in and try it A tire valve may drop your
pressure reading a bit more than the "proper" valve - some testers
uses special valves, some used regular tire valves - some long - some
short. Long will have less effect on the reading if it can be used
(softer spring)

On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:


"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

On Wed, 20 Mar 2013 19:59:49 -0400, wrote:

On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:


"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

On Mar 20, 6:04*pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
*A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

On Mar 20, 6:24*pm, jon_banquer wrote:
On Mar 20, 6:04*pm, Ed Huntress wrote:









On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
*A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

It's about doing a comparison. You're always going to have a
percentage of leak and you want about the same percentage of leak for
every cylinder.

Watch this. It's a well done video:

http://www.youtube.com/watch?v=QNf0IOIvIcY

On Mar 19, 9:35*pm, jon_banquer wrote:
On Mar 19, 9:31*pm, "Steve W." wrote:









Jim Wilkins wrote:
"Steve W." wrote in message
...
Oh the old unit uses nothing more than a bog standard air pressure
gauge with a "compression tester" face on it. The spark adapter
fittings are the part that makes it special.

Steve W.

If the check valve was further up the hose the dead space would lower
the reading.

I have units with the valve at the tip and one with the valve right at the gauge. No
difference in the readings but they ones at the adapters are easier to change out.

--
Steve W.

I like the ones that have a quality rubber condom around the gauge.

How soon before we start taking about what we use to check TDC?

Still waiting for how others check TDC. I bet my method is better and
more accurate. ;)

On Wed, 20 Mar 2013 18:24:12 -0700 (PDT), jon_banquer
wrote:

On Mar 20, 6:04*pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
*A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

I don't understand that. All you care about is the air you get into
the cylinder, right?

I used to do a lot of leakdown tests, and I think I remember how they
were done. All I did was pump the cylinder up to some pressure and
time how long it takes to drop to some lower pressure. Do the test
dry, then wet, in each cylinder. If it falls faster when dry, it's
rings. If it's the same time when wet, it's valves.

Am I missing something?

On Mar 20, 6:38*pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 18:24:12 -0700 (PDT), jon_banquer









wrote:
On Mar 20, 6:04 pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced..

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

I don't understand that. All you care about is the air you get into
the cylinder, right?

I used to do a lot of leakdown tests, and I think I remember how they
were done. All I did was pump the cylinder up to some pressure and
time how long it takes to drop to some lower pressure. Do the test
dry, then wet, in each cylinder. If it falls faster when dry, it's
rings. If it's the same time when wet, it's valves.

Am I missing something?

It's a percentage test with two gauges.

If you have cylinder(s) with major discrepancies you find out where
the air is leaking to.

If you hear air in the exhaust pipe it's a bad exhaust valve.

If you hear air in the intake it's a bad intake valve.

If you hear air in the crankcase (check where oil dipstick is) it's
bad piston rings.

On Wed, 20 Mar 2013 18:35:00 -0700 (PDT), jon_banquer
wrote:

On Mar 20, 6:24*pm, jon_banquer wrote:
On Mar 20, 6:04*pm, Ed Huntress wrote:









On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
*A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

It's about doing a comparison. You're always going to have a
percentage of leak and you want about the same percentage of leak for
every cylinder.

Watch this. It's a well done video:

http://www.youtube.com/watch?v=QNf0IOIvIcY

That's interesting, and I'm sure it's faster to use than the old ones.
From what he demonstrated, though, I see no way to identify ring
versus valve problems. I guess you could run the test wet as well with
that rig, but it's a different animal.

You could pump mine up with a bicycle pump, if you had to, but I
always had a little compressor handy.

--
Ed Huntress

On Mar 20, 6:49*pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 18:35:00 -0700 (PDT), jon_banquer









wrote:
On Mar 20, 6:24 pm, jon_banquer wrote:
On Mar 20, 6:04 pm, Ed Huntress wrote:

On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

It's about doing a comparison. You're always going to have a
percentage of leak and you want about the same percentage of leak for
every cylinder.

Watch this. It's a well done video:

http://www.youtube.com/watch?v=QNf0IOIvIcY

That's interesting, and I'm sure it's faster to use than the old ones.
From what he demonstrated, though, I see no way to identify ring
versus valve problems. I guess you could run the test wet as well with
that rig, but it's a different animal.

You could pump mine up with a bicycle pump, if you had to, but I
always had a little compressor handy.

--
Ed Huntress

Consider that you are going to have to take the engine apart if you
have "dead holes" anyway so the need for exact specifics doesn't
really matter that much. All you're really looking to see is if you
have "dead holes" and generally what the problem might be.

On Mar 20, 6:53*pm, jon_banquer wrote:
On Mar 20, 6:49*pm, Ed Huntress wrote:









On Wed, 20 Mar 2013 18:35:00 -0700 (PDT), jon_banquer

wrote:
On Mar 20, 6:24 pm, jon_banquer wrote:
On Mar 20, 6:04 pm, Ed Huntress wrote:

On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

It's about doing a comparison. You're always going to have a
percentage of leak and you want about the same percentage of leak for
every cylinder.

Watch this. It's a well done video:

http://www.youtube.com/watch?v=QNf0IOIvIcY

That's interesting, and I'm sure it's faster to use than the old ones.
From what he demonstrated, though, I see no way to identify ring
versus valve problems. I guess you could run the test wet as well with
that rig, but it's a different animal.

You could pump mine up with a bicycle pump, if you had to, but I
always had a little compressor handy.

--
Ed Huntress

Consider that you are going to have to take the engine apart if you
have "dead holes" anyway so the need for exact specifics doesn't
really matter that much. All you're really looking to see is if you
have "dead holes" and generally what the problem might be.

The problem with the method he shows is what happens when you don't
have a distributor to put each cylinder at TDC on the compression
stroke so the leak down test can be done. That's why I want to talk
about checking TDC and how others do it. ;)

On Wed, 20 Mar 2013 21:38:05 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 18:24:12 -0700 (PDT), jon_banquer
wrote:

On Mar 20, 6:04*pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
*A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

I don't understand that. All you care about is the air you get into
the cylinder, right?

I used to do a lot of leakdown tests, and I think I remember how they
were done. All I did was pump the cylinder up to some pressure and
time how long it takes to drop to some lower pressure. Do the test
dry, then wet, in each cylinder. If it falls faster when dry, it's
rings. If it's the same time when wet, it's valves.

Am I missing something?
I guess you can do it that way, but it's not terribly effective or
accurate. A normal leakdown tester feeds 80psi to one side of a
restriction, which feeds the air into the cyl. Guage on inlet
(generally 80 psi) and on the cyl side. With no leakage at all you get
80/80. If you have a small leakdown (normal) you may have 80/75. A
sognificant leak may give you 80/60 or 80/50.

Then you listen in the intake, exhaust, and crankcase to tell where
the air is going.

On Wed, 20 Mar 2013 18:45:39 -0700 (PDT), jon_banquer
wrote:

On Mar 20, 6:38*pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 18:24:12 -0700 (PDT), jon_banquer









wrote:
On Mar 20, 6:04 pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

I don't understand that. All you care about is the air you get into
the cylinder, right?

I used to do a lot of leakdown tests, and I think I remember how they
were done. All I did was pump the cylinder up to some pressure and
time how long it takes to drop to some lower pressure. Do the test
dry, then wet, in each cylinder. If it falls faster when dry, it's
rings. If it's the same time when wet, it's valves.

Am I missing something?

It's a percentage test with two gauges.

If you have cylinder(s) with major discrepancies you find out where
the air is leaking to.

If you hear air in the exhaust pipe it's a bad exhaust valve.

If you hear air in the intake it's a bad intake valve.

If you hear air in the crankcase (check where oil dipstick is) it's
bad piston rings.

OK, I can see where that's a lot faster, and it actually combines the
equivalent of a regular compression test (sort of) and an
old-fashioned leak-down test.

With the older equipment, you only would do a leak-down test if all
cylinders looked good in the regular test but you had some reason to
believe one or more cylinders still had a problem. You could do both
tests dry and then wet to try to isolate the problem a bit; pressure
loss with a wet cylinder meant a valve or head-gasket problem, so you
had to pull the head in either case.

The only thing I see wrong with the newer device is that it only
checks the rings at TDC, while a conventional compression test will
show a cylinder is off from any problem along the whole stroke -- like
a scored cylinder that isn't scored along the full length of the
stroke (an engine that's been over-revved a lot, or which has a
cracked lower ring). Also, a valve that's out of adjustment, or which
has a sticky lifter, but which is still fully closed at TDC on the
compression stroke, will not show you the valve problem.

Anyway, it's not something I'm likely to do again. I just thought,
mistakenly, that the OP might have been looking at an old-style
leak-down tester. It appears that it was just a missing Schrader valve
stem in a conventional compression tester. That's what we save old
bicycle inner-tubes for -- spare Schrader stems, and gasket material.

--
Ed Huntress

On Wed, 20 Mar 2013 18:53:49 -0700 (PDT), jon_banquer
wrote:

On Mar 20, 6:49*pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 18:35:00 -0700 (PDT), jon_banquer









wrote:
On Mar 20, 6:24 pm, jon_banquer wrote:
On Mar 20, 6:04 pm, Ed Huntress wrote:

On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

It's about doing a comparison. You're always going to have a
percentage of leak and you want about the same percentage of leak for
every cylinder.

Watch this. It's a well done video:

http://www.youtube.com/watch?v=QNf0IOIvIcY

That's interesting, and I'm sure it's faster to use than the old ones.
From what he demonstrated, though, I see no way to identify ring
versus valve problems. I guess you could run the test wet as well with
that rig, but it's a different animal.

You could pump mine up with a bicycle pump, if you had to, but I
always had a little compressor handy.

--
Ed Huntress

Consider that you are going to have to take the engine apart if you
have "dead holes" anyway so the need for exact specifics doesn't
really matter that much. All you're really looking to see is if you
have "dead holes" and generally what the problem might be.

I'm sure it's a practical solution or they wouldn't go to that
complication. And in a commercial shop, time is money, and the old way
of running those tests could take a whole Saturday morning. If it was
a Bristol or a Jag engine, it was worth the play time. Otherwise, not.

God save me from ever having to do a hot valve-lash job on a
six-cylinder Triumph again...

--
Ed Huntress

On Mar 20, 7:14*pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 18:53:49 -0700 (PDT), jon_banquer









wrote:
On Mar 20, 6:49 pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 18:35:00 -0700 (PDT), jon_banquer

wrote:
On Mar 20, 6:24 pm, jon_banquer wrote:
On Mar 20, 6:04 pm, Ed Huntress wrote:

On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

It's about doing a comparison. You're always going to have a
percentage of leak and you want about the same percentage of leak for
every cylinder.

Watch this. It's a well done video:

http://www.youtube.com/watch?v=QNf0IOIvIcY

That's interesting, and I'm sure it's faster to use than the old ones.
From what he demonstrated, though, I see no way to identify ring
versus valve problems. I guess you could run the test wet as well with
that rig, but it's a different animal.

You could pump mine up with a bicycle pump, if you had to, but I
always had a little compressor handy.

--
Ed Huntress

Consider that you are going to have to take the engine apart if you
have "dead holes" anyway so the need for exact specifics doesn't
really matter that much. All you're really looking to see is if you
have "dead holes" and generally what the problem might be.

I'm sure it's a practical solution or they wouldn't go to that
complication. And in a commercial shop, time is money, and the old way
of running those tests could take a whole Saturday morning. If it was
a Bristol or a Jag engine, it was worth the play time. Otherwise, not.

God save me from ever having to do a hot valve-lash job on a
six-cylinder Triumph again...

--
Ed Huntress

Many commercial auto repair shops don't even know what a leak down
test is and all they know and do are compression tests.

On Wed, 20 Mar 2013 21:56:51 -0400, wrote:

On Wed, 20 Mar 2013 21:38:05 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 18:24:12 -0700 (PDT), jon_banquer
wrote:

On Mar 20, 6:04*pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...

I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...

--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.

Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.

I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
*A leakdown tester should have 2 guages and WILL have a connector for
compressed air.

Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.

What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).

Is there something else that I've missed?

--
Ed Huntress

One gauge tells you your air input pressure, the other your cylinder
pressure.

I don't understand that. All you care about is the air you get into
the cylinder, right?

I used to do a lot of leakdown tests, and I think I remember how they
were done. All I did was pump the cylinder up to some pressure and
time how long it takes to drop to some lower pressure. Do the test
dry, then wet, in each cylinder. If it falls faster when dry, it's
rings. If it's the same time when wet, it's valves.

Am I missing something?
I guess you can do it that way, but it's not terribly effective or
accurate. A normal leakdown tester feeds 80psi to one side of a
restriction, which feeds the air into the cyl. Guage on inlet
(generally 80 psi) and on the cyl side. With no leakage at all you get
80/80. If you have a small leakdown (normal) you may have 80/75. A
sognificant leak may give you 80/60 or 80/50.

Then you listen in the intake, exhaust, and crankcase to tell where
the air is going.

Yeah, I can see that it's very quick to diagnose several problems. But
watch out what you call "normal." g Unless I'm mistaken, those
two-gauge deals didn't exist when I was club racing, in the late '60s
and early '70s. At least, it wasn't equipment that we bottom-dollar
sports car types had. The ones we used were "normal" then.

I do see a limitiation of this newer device, compared to the old ones,
however. I described it in one of my posts to Jon.

--
Ed Huntress

On Wed, 20 Mar 2013 22:03:57 -0400, BQ340
wrote:

On 3/20/2013 9:49 PM, Ed Huntress wrote:


That's interesting, and I'm sure it's faster to use than the old ones.
From what he demonstrated, though, I see no way to identify ring
versus valve problems. I guess you could run the test wet as well with
that rig, but it's a different animal.

You could pump mine up with a bicycle pump, if you had to, but I
always had a little compressor handy.



You would use a stethoscope to locate where the leak is.

Valve leaks you would hear in the exhaust or carb. Ring leaks you would
hear in the dipstick tube.


MikeB

It's very interesting and it looks slick. I'm sure one would be on my
Christmas list if I were 45 years younger. d8-)

--
Ed Huntress

On Wed, 20 Mar 2013 12:39:24 -0400, John
wrote:

Ed Huntress wrote:
On Wed, 20 Mar 2013 21:56:51 -0400, wrote:

On Wed, 20 Mar 2013 21:38:05 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 18:24:12 -0700 (PDT), jon_banquer
wrote:

On Mar 20, 6:04 pm, Ed Huntress
wrote:
On Wed, 20 Mar 2013 19:59:49 -0400,
wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:

On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:

"Ken Grunke" wrote in message
...



I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve.
That is what I am missing. It may be a fitting I had,
but absent-mindedly misplaced.

Could be a spring and or check ball is missng or gunked
up at the spark plug fitting end...

--FWIW blowing into the end with your mouth probably
won't produce enough hose expansion to actuate a ball
type check valve.

Sorry for jumping into the middle without having read the
thread, but there are two kinds of compression testers:
the regular kind, which have a button to activate the
check-release valve; and leak-down testers, which have no
such valve.

I have both. They look almost the same. Perhaps, if Ken's
tester doesn't have a check valve, he has a leakdown
tester. If so, it will have a spark-plug-thread terminal
end. Regular testers *may* have such a thread. Mine just
has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a
connector for compressed air.

Mine has one gauge. It's around 45 years old. And as I noted
in an addition to the post above, it has a Schrader valve for
pumping up the cylinder.

What's the second gauge for? With mine, you just attach it,
make sure both valves are closed, and pump it up. Test dry,
then test wet (with about an ounce of oil in the cylinder;
more for a V-engine).

Is there something else that I've missed?

-- Ed Huntress

One gauge tells you your air input pressure, the other your
cylinder pressure.

I don't understand that. All you care about is the air you get
into the cylinder, right?

I used to do a lot of leakdown tests, and I think I remember how
they were done. All I did was pump the cylinder up to some
pressure and time how long it takes to drop to some lower
pressure. Do the test dry, then wet, in each cylinder. If it
falls faster when dry, it's rings. If it's the same time when
wet, it's valves.

Am I missing something?
I guess you can do it that way, but it's not terribly effective or
accurate. A normal leakdown tester feeds 80psi to one side of a
restriction, which feeds the air into the cyl. Guage on inlet
(generally 80 psi) and on the cyl side. With no leakage at all you
get 80/80. If you have a small leakdown (normal) you may have
80/75. A sognificant leak may give you 80/60 or 80/50.

Then you listen in the intake, exhaust, and crankcase to tell
where the air is going.

Yeah, I can see that it's very quick to diagnose several problems.
But watch out what you call "normal." g Unless I'm mistaken, those
two-gauge deals didn't exist when I was club racing, in the late
'60s and early '70s. At least, it wasn't equipment that we
bottom-dollar sports car types had. The ones we used were "normal"
then.

I do see a limitiation of this newer device, compared to the old
ones, however. I described it in one of my posts to Jon.



The leakdown testers were used in aviation. The calibrated leak in the
tester has a spec. for hole size and length as well as other
dimensions. There are more than one size of calibrated leak. For
larger cylinders such as a 200 Cu In on a 1820 Wright you had to use a
larger calibrated leak gauge or every reading would indicate a bad cylinder.

http://en.wikipedia.org/wiki/Leak-down_tester


John

Very interesting. Thanks, John.

--
Ed Huntress

Ed Huntress wrote:
On Wed, 20 Mar 2013 18:45:39 -0700 (PDT), jon_banquer
wrote:

On Mar 20, 6:38 pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 18:24:12 -0700 (PDT), jon_banquer









wrote:
On Mar 20, 6:04 pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:
On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:
"Ken Grunke" wrote in message
...
I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.
Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...
--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.
Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.
I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a connector for
compressed air.
Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.
What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).
Is there something else that I've missed?
--
Ed Huntress
One gauge tells you your air input pressure, the other your cylinder
pressure.
I don't understand that. All you care about is the air you get into
the cylinder, right?

I used to do a lot of leakdown tests, and I think I remember how they
were done. All I did was pump the cylinder up to some pressure and
time how long it takes to drop to some lower pressure. Do the test
dry, then wet, in each cylinder. If it falls faster when dry, it's
rings. If it's the same time when wet, it's valves.

Am I missing something?
It's a percentage test with two gauges.

If you have cylinder(s) with major discrepancies you find out where
the air is leaking to.

If you hear air in the exhaust pipe it's a bad exhaust valve.

If you hear air in the intake it's a bad intake valve.

If you hear air in the crankcase (check where oil dipstick is) it's
bad piston rings.

OK, I can see where that's a lot faster, and it actually combines the
equivalent of a regular compression test (sort of) and an
old-fashioned leak-down test.

With the older equipment, you only would do a leak-down test if all
cylinders looked good in the regular test but you had some reason to
believe one or more cylinders still had a problem. You could do both
tests dry and then wet to try to isolate the problem a bit; pressure
loss with a wet cylinder meant a valve or head-gasket problem, so you
had to pull the head in either case.

The only thing I see wrong with the newer device is that it only
checks the rings at TDC, while a conventional compression test will
show a cylinder is off from any problem along the whole stroke -- like
a scored cylinder that isn't scored along the full length of the
stroke (an engine that's been over-revved a lot, or which has a
cracked lower ring). Also, a valve that's out of adjustment, or which
has a sticky lifter, but which is still fully closed at TDC on the
compression stroke, will not show you the valve problem.

Anyway, it's not something I'm likely to do again. I just thought,
mistakenly, that the OP might have been looking at an old-style
leak-down tester. It appears that it was just a missing Schrader valve
stem in a conventional compression tester. That's what we save old
bicycle inner-tubes for -- spare Schrader stems, and gasket material.


Actually you can use a leak-down tester through the entire stroke IF you have the proper
tools to rotate the crank.

For a very fast way of checking for a dead hole in an engine you don't use a compression
tester anyway. Toss a scope on there. One channel will use an inductive pick-up on the pos
battery lead. The other goes to any plug wire. One channel gets set to measure the amp
flow and the other acts as a trigger. Pull the power to the injectors or unhook the fuel
line or pump so the engine doesn't start. Then crank it over with the starter and look at
the amp readings. If all the holes are good you will see nice even amp draws across the
engine. Any cylinder not pulling it's share will show as decreased amp draw.

To see it in action - http://www.youtube.com/watch?v=WKdZsWU2ZmI

--
Steve W.

On Thu, 21 Mar 2013 02:19:21 -0400, "Steve W."
wrote:

Ed Huntress wrote:
On Wed, 20 Mar 2013 18:45:39 -0700 (PDT), jon_banquer
wrote:

On Mar 20, 6:38 pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 18:24:12 -0700 (PDT), jon_banquer









wrote:
On Mar 20, 6:04 pm, Ed Huntress wrote:
On Wed, 20 Mar 2013 19:59:49 -0400, wrote:
On Wed, 20 Mar 2013 11:49:22 -0400, Ed Huntress
wrote:
On Wed, 20 Mar 2013 08:42:16 -0700, "PrecisionmachinisT"
wrote:
"Ken Grunke" wrote in message
...
I am assuming there has to be a separate check valve INLINE between the
plug adapter and the gauge below the release valve. That is what I am
missing. It may be a fitting I had, but absent-mindedly misplaced.
Could be a spring and or check ball is missng or gunked up at the spark plug
fitting end...
--FWIW blowing into the end with your mouth probably won't produce enough
hose expansion to actuate a ball type check valve.
Sorry for jumping into the middle without having read the thread, but
there are two kinds of compression testers: the regular kind, which
have a button to activate the check-release valve; and leak-down
testers, which have no such valve.
I have both. They look almost the same. Perhaps, if Ken's tester
doesn't have a check valve, he has a leakdown tester. If so, it will
have a spark-plug-thread terminal end. Regular testers *may* have such
a thread. Mine just has a tapered rubber plug.
A leakdown tester should have 2 guages and WILL have a connector for
compressed air.
Mine has one gauge. It's around 45 years old. And as I noted in an
addition to the post above, it has a Schrader valve for pumping up the
cylinder.
What's the second gauge for? With mine, you just attach it, make sure
both valves are closed, and pump it up. Test dry, then test wet (with
about an ounce of oil in the cylinder; more for a V-engine).
Is there something else that I've missed?
--
Ed Huntress
One gauge tells you your air input pressure, the other your cylinder
pressure.
I don't understand that. All you care about is the air you get into
the cylinder, right?

I used to do a lot of leakdown tests, and I think I remember how they
were done. All I did was pump the cylinder up to some pressure and
time how long it takes to drop to some lower pressure. Do the test
dry, then wet, in each cylinder. If it falls faster when dry, it's
rings. If it's the same time when wet, it's valves.

Am I missing something?
It's a percentage test with two gauges.

If you have cylinder(s) with major discrepancies you find out where
the air is leaking to.

If you hear air in the exhaust pipe it's a bad exhaust valve.

If you hear air in the intake it's a bad intake valve.

If you hear air in the crankcase (check where oil dipstick is) it's
bad piston rings.

OK, I can see where that's a lot faster, and it actually combines the
equivalent of a regular compression test (sort of) and an
old-fashioned leak-down test.

With the older equipment, you only would do a leak-down test if all
cylinders looked good in the regular test but you had some reason to
believe one or more cylinders still had a problem. You could do both
tests dry and then wet to try to isolate the problem a bit; pressure
loss with a wet cylinder meant a valve or head-gasket problem, so you
had to pull the head in either case.

The only thing I see wrong with the newer device is that it only
checks the rings at TDC, while a conventional compression test will
show a cylinder is off from any problem along the whole stroke -- like
a scored cylinder that isn't scored along the full length of the
stroke (an engine that's been over-revved a lot, or which has a
cracked lower ring). Also, a valve that's out of adjustment, or which
has a sticky lifter, but which is still fully closed at TDC on the
compression stroke, will not show you the valve problem.

Anyway, it's not something I'm likely to do again. I just thought,
mistakenly, that the OP might have been looking at an old-style
leak-down tester. It appears that it was just a missing Schrader valve
stem in a conventional compression tester. That's what we save old
bicycle inner-tubes for -- spare Schrader stems, and gasket material.


Actually you can use a leak-down tester through the entire stroke IF you have the proper
tools to rotate the crank.

So you have to back off the rocker arms or remove the camshaft?


For a very fast way of checking for a dead hole in an engine you don't use a compression
tester anyway. Toss a scope on there. One channel will use an inductive pick-up on the pos
battery lead. The other goes to any plug wire. One channel gets set to measure the amp
flow and the other acts as a trigger. Pull the power to the injectors or unhook the fuel
line or pump so the engine doesn't start. Then crank it over with the starter and look at
the amp readings. If all the holes are good you will see nice even amp draws across the
engine. Any cylinder not pulling it's share will show as decreased amp draw.

To see it in action - http://www.youtube.com/watch?v=WKdZsWU2ZmI

Yeah, I've seen descriptions of that.

--
Ed Huntress