Engine compression

[Marty87]

Hey lads i have a mercruiser 4.3L v6 (190) 2001 it's has 556 hours on her and when I get home I am going to be doing compression test on each Cylinder what sort of compression I'm i looking to get of each cylinder for a gd engine

[mmwjr]

Around 150 ft lbs and all cylinders should be within 10% of each other.

If you get a reading of 100 ft lbs or less engine work is in order.

[bman440440]

I'm at 290 hours now and all mine on my 4.3 are from 180-183 PSI cold (and yes it is a known good compression tester)... but what ever yours are they should be 10% of each other.

[mmwjr]

Originally Posted by mmwjr

Around 150 ft lbs and all cylinders should be within 10% of each other.

If you get a reading of 100 ft lbs or less engine work is in order.

Duh foot lbs is torque I meant psi (pounds per square inch)

[stock333]

In order to do a compression test do i need to remove all plugs or can i do 1 by one

Thanks

[mmwjr]

Originally Posted by stock333

In order to do a compression test do i need to remove all plugs or can i do 1 by one

Thanks

First warm the engine then remove all plugs to perform the test.