RPM's & Prop

[Genie Aye]

If I had 100 comp on any cylinder and it is more than 10% lower than my highest---bad cylinder/s.

With only 100lbs comp--I would wonder what type of freshen up your mechanic did--almost sounds like some ports may hooked the rings from burr's.

I can tell you with a injector out on my engine--I lost about 10 mph on the top end--that is a engine rated at 218 at the prop.

Good luck--but the news you are giving is NOT good.

Bummed for ya.

[Joker2]

You guys are scaring me, but I am not surprised with this guy. If it means anything, I did the test on a cold engine, only taking one plug out at a time, I did the test when I was troubleshooting my problem. At that point I had a bad ignition coil only firing on 5 cyl. I know this wasn't the proper way to do a Comp. test, but do you think it would make that much difference. I don't know. For what it is worth ( nothing ) he told me the engine was good when he got it, that he just changed the crank. Maybe now that it is running nice I'll do the test again. Thanks for all your input.

[aussie]

Originally Posted by Joker2

You guys are scaring me, but I am not surprised with this guy. If it means anything, I did the test on a cold engine, only taking one plug out at a time, I did the test when I was troubleshooting my problem. At that point I had a bad ignition coil only firing on 5 cyl. I know this wasn't the proper way to do a Comp. test, but do you think it would make that much difference. I don't know. For what it is worth ( nothing ) he told me the engine was good when he got it, that he just changed the crank. Maybe now that it is running nice I'll do the test again. Thanks for all your input.

recheck your comp with all plugs out 100psi is too low in my eyes they guys are 100% rite to much variation on comp i only like 5 psi or 10 psi max difference could be broken top ring good luck