Compression testing help.

[84250r]

When compression testing. Are you suppose to have the exhaust and carb on? What is average compression for a 85 tri z?

[J.D.]

Thread the reader in the hole good, hold the throttle wide open, give it 5 strong kicks. Leave the exhaust, carb, all that crap on. I think you're supposed to be around 180 PSI.

[plkmonster2]

yup, make sure you have it all on, or you could get a false reading. 180 seams high, but maybe not for a z.

[84250r]

Thanks guys.

[3 weelin geezer]

I have a question. Where are possible compression leaks? I have new piston, new head gasket. I had my piston replaced because of a scored cyl. and had it working for a ride but it still smoked. Then, I changed out the timing chain and cyl gasket. I tightened the nuts to 15 ft-lb. It now only shows 30-35 psi and won't start.

[J.D.]

Well, I'm assuming you also put new rings in too right? Probably what's going on is the new rings haven't had a chance to "seat"(conform to the cylinder) yet, and this will cause low compression until they're seated in good.

[samster143]

3wheelingeezer, Do you also have a TRI-Z? I ask because you mention a timing chain.

[twgranger]

3wheelingeezer, Do you also have a TRI-Z? I ask because you mention a timing chain.I think he has a 198? honda 185s. :?

[3 weelin geezer]

No, mines a '81 atc 185s that was bored out , scratched because of the previous owners home made k&n shop rag filter minus the oil so I had it bored out again to something like a 200- 210 cc. done at the dealership with a new piston and rings. What I find frustrating is that I think it ran before I started monkeying around with the timing chain thing. But, that wouldnt cause such low compression as I see it. My timeing light shows the timing is ok. It is pull started which may be good for losing weight but it still won't start. Here is a picture before I changed all this stuff. Smoked like an old west train. I consulted with a local mechanic who also owns a 185 s and he told me that it was probably all the leftover oil in the muffler that has been burning and that I should run it for a tank of gas before I do anything else to it to 'fix' it. The other atv I bought in Sep. is a new kawasaki bayou. But it is for my brother who looked like he was going to pass out when I told him it was a present for him. Too bad I didn't have my camera handy. Kinda like a cop as they say, never around when you need it. LOL.