Thread: Engine Compression

Its more important that they be close to each other. No more than 15 lbs difference between any 2 cylinders.

Even if they're down at 65? Is that too low? Or does that not matter as long as they're all close?

Originally Posted by pvasst1

Even if they're down at 65? Is that too low? Or does that not matter as long as they're all close?

No 65 is too low. They should be 100lbs or higher. Unfortunately manufacturers do not give an average compression for motors when they are new. It sure would make it easier to determine the condition of a motor if they could. If they are all reading that low I would try a different gauge to be sure.

That's what I was told, checked by a mechanic all were 65. And the mechanic said the motor was perfect and that's why those motors lasted so long was because the compression was so low on them. I don't have any reason to believe I was being misled I just didn't know how much compression they were supposed to have.

Will the motor run? Reason I am asking is....I don't see how it can even start with compression that low.

Yeah starts and runs like a champ.

I would run it then. If it ain't broke don't try to fix it, Lol. :D

I'm just trying to not put myself in a position where I buy something that I can't afford to fix if something happens