DropTopBird

iTrader: (17)

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.

M1SERY

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.

DropTopBird

iTrader: (17)

Thanks for the info. I am curious if anyone knows what the psi was around new so I can gauge relatively how healthy the engine is.

LilJayV10

iTrader: (39)

I'm going to say 170-180. As mentioned its the consistency between all cylinders is what important. Unless all of them are 100.

c-bolt

iTrader: (1)

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.