Compression Per Cylinder
Compression Per Cylinder Just curious as to what a good compression psi would be for each cylinder. My motor just clicked over to 125k and I am going to do a compression check to make sure everything is still good. Thanks guys.
Launching!
Joined: Oct 2012
Posts: 219
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From: near Beech Bend race way
This will help, The highest and lowest shouldn’t vary by more than 15 percent. If one or more of the cylinders reads well below the rest, use a trigger-type oil can to send a good squirt of motor oil down the spark plug opening, and retest the compression of that cylinder with the gauge. If the reading is the same, the valves either are worn (and letting pressure escape) or are out of adjustment. If the reading rises dramatically after you insert the oil, you probably need new rings on the piston in that cylinder. If the pressure recorded by the gauges is less than 100 psi, the cylinder definitely isn’t mechanically sound.
It can all depend on your compression tester too. I had two different testers that were 20-30 lbs apart from each other. If you get really low numbers, try another tester, but consistency between cylinders is key for sure.
