Testing compression testers

[Hammermechanicman]

Needed a new compression tester for bigger engines and auto engines. After a little research i picked up the Innova 3612. I specifically chose this one because it has the Schrader valve at tbe very end of the spark plug adapter. Like my small engine compression tester
Using both of these in the same 90cc chainsaw the readings are the same

Compare this with a cheap Ebay tester.

The cheap chineese tester has a crappy valve that is not at the very end of the spark plug adapter. If someone is looking to get a compression tester for small engines may want to pass on the cheap chineese ones.

 

[PTmowerMech]

My HF one was getting off. Releasing the pressure, it was drop down to about 10lbs. So, I took it apart, bent the mechanism so that the dial would be at zero again. I didn't feel comfy with this, so I went to the parts store and bought a new one. (probably cheap chinese one).
Tested the same engine that read right on 120lbs. Put the old one back on it, and guess what. It also read 120lbs.
LMAO.. So now I have two cheap chinese ones.

 

[bertsmobile1]

Note in the photos that the good tester has the makers name printed on the dial
The bad one looks identical but without the name
Goes back to the advice about buying aftermarket parts
If the maker / distributor / retailer has their name on it then it is most likely good.
If there is none, it is so bad the maker does not want any one to find out who made it .

 

[Hammermechanicman]

So true. So true.

 

[7394]

Reliable tools are key to do the most accurate work.