i know how to do a compression test and i've read about the oil seals in a 2 stroke not sealing and causing running problems, but i have a question about compression readings. on a 2 stroke if you do a compression test. will the gauge still register the correct value if you have bad seals. my thinking is that it would and the seals would only show up if you did a bleed down test. i was getting around 100 psi and my trail boss 250 wouldn't idle and was very hard to start. i ordered a new top end rebuild kit with a 20 over piston and will put it in as soon as it arrives. i also ordered seal but would like to know what to expect.

 

Your seals(good or bad) will not affect the reading from a compression test.

 

94harley thank you. i didn't think so but i am so new to 2 strokes. i just want to do this right.

 

just need to do a compression test w/ a cold engine and the throttle wide open for best results. as mentioned it wouldnt effect it. also that is about the min. compression you would want to run with. imo