Compression Tester

[inspectorwoody]

Is there a different compression tester made just for small engines or will one you use for vehicles work just fine?

Thanks

Gadget

[Cut4fun]

I use a $25 one that is made for both and can be bought at wally world or advanced auto . You just have to leave the brass adpater off  for checking small engines and screw it straight in without the brass adapters. Has alway worked and been accurate for me.

[sawguy21]

I have an old automotive tester that works fine most of the time. However I don't have adapters to fit the newer mini plug threads. On two strokes I pull the muffler to check for scoring and check the compression by feel.

[rebocardo]

I tried using my car compression tester on my Husky 3120 and I could not get  it beyond 75 psi because of the resistance. Pulling with two hands with both feet on the saw I could barely pull the cord with  the compression relief valve off.

[sawguy21]

 :D :D :D :D

[macpower]

Just be aware that most small 4 stroke engines have a compression relief. What you get for a reading may or may not have any significance. Best diagnosis would be done with a leak down test.
Whatever you use, on an L head engine, be sure that the adapter does not extend too far through the head as it may crash the valves.
On 2 stroke be sure your tester has a good schrader valve in it. Displacement volume is so small that some of the automotive styles with long hoses will require a lot of pulling to get a good reading.