stock compression?

[illMATTic]

what should the stock compression be on an 86 merc 2.4? all of my readings were about 108. is this low? i have heard of newer moters having 130 psi. should i get a second gauge and try it again since they were all exactly the same?

[crazy horse]

I would check it with a second gauge for the hell've it. Around 125 lb's is better but all the same pressure is very good. ;)

[illMATTic]

would this be evident of a large puff of smoke upon starting it warm? i have nothing to compare it to since i have never run a 200 before.

[T-REX]

My stock 2.4 had 135#s...Chrome motor...

The puff ov smoke tells nuth'in about the loss ov compression...Y kan go from 135#s to 110#s, and never reelize it, kuz it happens so slow...U may notice a lil less grunt, or that U've lost a MPH or 2 on top, but It happens in such a slow manner, It's not sumpth'in that U feel happen'in...When U rebuild a week motor, U kan feel the extra power, which iz not reely extra, but wuz there before it started loos'in compression!!...

That smoke iz a good sign...smoke iz your fren!!!

[illMATTic]

i took these readings when the motor was cold. should it be warm to get an acurate reading?

[Rickracer]

All of the above will bump the numbers up a bit. A better indicator of the condition of your cylinder sealing would be a leakdown test. :cool:

[GatorBaiter]

I would build a leak down tester like in the June issue of Bass and Walleye boats magazine. That gives a better idea of how your cylinders are sealing up. I have 3 compression testers and they all give a different reading, sometimes over 10 psi. GB

[GatorBaiter]

:d :d :d