Compression Tester Fail?

[Moss Man]

A couple years back I wanted to add a decent compression gauge to my arsenal and through discussion here and with friends, I settled on the Lisle tester;

Up until yesterday it had been a rock solid investment and it still might be. I was testing a Husky XP saw that should have been around 150 lbs and it read 125. In a panic I grabbed a 262XP that had tested 170 lbs last time I checked it, it now read 135 lbs. In a greater panic I ran to the storage room to grab the high compression Walkerized 394XP which I know for a fact has over 200 lbs compression, it read just over 155 lbs. Damn.

One change that comes to mind is that the area where I now test, my garage, isn't heated and being in Maine the temp in there now is from 10-35 degrees fahrenheit. The area I had a shop in at my old house was always around 70 degrees and everything seemed fine.

The saws are cold, the air is cold.......real cold.

The only other thing I can think of is that the last time I used the tester I accidentally left pressure in the gauge, probably 150 lbs. Do these gauges have liquid of any kind in them? Somehow I doubt it, but what do I know.

I am not sure where to go with this just yet. I have a friend with a Stihl dealership, I'll bring the gauge there and have him compare it to his.

The shop will be heated in the future, I just haven't had the time or money to get the chimney for the large woodstove I have for it. I have some saws to compression test, I am liquidating my collection to a point.........so far I have picked 4-5 that should never leave here.

 

[WVshooter]

The only other thing I can think of is that the last time I used the tester I accidentally left pressure in the gauge, probably 150 lbs. Do these gauges have liquid of any kind in them? Somehow I doubt it, but what do I know.

I'd say there's your problem. How long was the pressure left in it?

Just to check, bring the gauge inside until all the internals have the chance to warm up, say, overnight. Then try the test with the warm gauge. Perhaps the cold has affected the internals temporarily. Good luck!

 

[PB]

I would bring it inside and let it warm up. You have had some moisture build up and freeze, but I don't know. I have the Accu___ from Sears and it has been good to me for the past 6 or 7 years.

 

[mikefunaro]

I've ruined a lot of the cheap $5 rotary dial tire pressure gauges leaving them in my car over the winter. They come out and they display 20% or so lower than they should. They do not seem to come back to life.

 

[Moss Man]

Yeah, I have dumped so much loot into getting the garage rebuilt and insulated that I can't afford the final phaze........heat.

I had my repair shop in my cellar at the last house and it was 10 feet from the woodstove. Everything was good there.

Moving has provided one good thing though, a huge open area for the next GTG. The firewood processor will be set up and running along with all the other little inventions.

I'll bring the tester inside right now. I am real leary of it now though.

 

[PB]

...... a huge open area for the next GTG.

Hmmm.......when is this GTG you speak of?

 

[pioneerguy600]

At worst you only may need to replace the dial gauge its self. It may have some moisture in it that froze or frosted up. A good thaw and dry out may bring it back if it has not sat too long and rusted internally.
Pioneerguy600

 

[nmurph]

i had a similar problem with my actron gauge. i replaced the shrader valve and i haven't had any more problems.

 

[vhmtach38]

The Schrader valve is probably worn and is available at NAPA
it is by Balkamp #BK-7009556. Color is white.

 

[Blowncrewcab]

If it's a Bordon tube type gauge it could be affected by leaving pressure in it, even more so in the drasticly changed weather conditions. I'd buy a new schrader valve and good quality liquid filled gauge, then you'll have a good accurate setup.

 

[Moss Man]

Hmmm.......when is this GTG you speak of?

Preferedly when the weather is nice and warm! Fall would actually be the best time for me. All my equipment, including the log loader, should be available. It'd be nice to see groundie do some log chopping this time. Another Barbecue would be kool.
There's plenty of space here for camping.

 

[galde]

The shrader valve in the threaded end of the hose that screws into the spark plug hole is just like the core valve in a tire, except that it has a very weak spring that holds the valve closed. The valve can get sticky from fuel mix that accumulates on it. This can cause an erroneous reading on the gauge, since it will require extra pressure to force the valve open to let the pressure build up in the hose. Most gauges have the same shrader valve in the pressure release. You can swap the two valves, replace the sticky one, or clean the sticky one with a solvent.

 

[Cantdog]

Hey Moss good to hear from you!! When I have a compression tester issue/question, I hook it to a known air supply. Most of the guages I use in the shop read very close to the same at any given pressure so if the comp guage doesn't it takes a hike. Perhaps yours if just cold and slow...LOLOL perhaps you are too in these temps!!!! (pulling I meanLOL) Anyway warm it up, dry it out and check it against your air compressor. This may not be totally accurate but will give you an idea what's going on. Should be pretty darn close.

A GTG sounds good to me......keep us informed!!!

 

[rolloman]

The Schrader valve is probably worn and is available at NAPA
it is by Balkamp #BK-7009556. Color is white.

Is that schrader valve special with a lighter spring or something different to be used in compression guages.

 

[nmurph]

Is that schrader valve special with a lighter spring or something different to be used in compression guages.

yes, the ones from a tire valve will read low bc the spring is too stiff.

 

[Arrowhead]

i had a similar problem with my actron gauge. i replaced the shrader valve and i haven't had any more problems.

:agree2: I have the same Lisle gauge as the op. It's only 5 months old and it started the same thing. I removed the schrader valve and cleaned it with wd-40, I also removed the gauge and blew air through it with the compressor. Put it back together and it was accurate again. Maybe a piece of carbon or something was floating around the valve?

 

[mdavlee]

I've had 2 start not holding pressure in the last few weeks. One was an actron and it just quit holding over 150 lbs. When it hits that it hisses. The new one from oreillys won't hold pressure. It reads and starts dropping down. I guess I'll take the new one back tomorrow as it's still under warranty.

 

[wendell]

How do you test your gauge to make sure it is accurate?

 

[mdavlee]

Regulated air compressor should work. That would be the easiest at home test I think.

 

[Arrowhead]

How do you test your gauge to make sure it is accurate?

The best method I have found is using a rubber tipped blowgun off the air compressor. I have an accurate regulator on the wall, I set it at say 120lbs. Then I stick the rubber tip of the blowgun in the gauge and see what it reads.