Analyze my compression test please...

Just did a static compression check. All cylinders had 125 psi (and leaked pressure somewhat quickly after stopping the engine turnover). Had a couple dark, oily plugs (uh-oh...) that went to 130 and held pressure.

Thoughts?

Usually, compression testers have a check-valve that doesn't allow pressure to leak back into the cylinders.

Does your tester not have a check-valve or did you remove it?

Also, even "good" cylinders leak down after a relatively short time.

That said, if the compression is Ok according to engine specifications and within around 10% cylinder-to-cylinder, highest to lowest, your rings "may" be Ok.

A test is squirting some oil in the cylinder and retesting to see if there is an appreciable rise in PSI.

The oil-burning "may" instead be as result of valve-seals, worn valve-guides, leaking intake-manifold gasket, etc

I had similar results on an engine I tested a couple months back. Though the engine had had a complete valve job with new seals around 8-months earlier, I replaced the valve-seals and that stopped the oil burning.

Another Moparts member recently had an intake manifold, leaking oil from the underside into the cylinders.

what motor did you do the test on? i got a 73 valiant all stock with a 318, 80,000 miles on it and did a comp. test in my auto tech class and i had an average of 145 psi.

Check your compression tester, it should have a check valve in it so the gauge stays at the highest reading until you release the pressure manually. I found when I tried my comp tester it was leaking down so I had to redo the gauge connection on it with teflon tape. Now the reading doesn't leak down anymore and the cylinders read 10psi higher.

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what motor did you do the test on? i got a 73 valiant all stock with a 318, 80,000 miles on it and did a comp. test in my auto tech class and i had an average of 145 psi.

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TA Care's altitude of 6000 ft puts a 120psi cranking pressure the equivilent of 150 psi at sea level, with certain engine assumptions, but, you get the jist of the difference.

The cylinders that had 130 and held pressure tells me there is a valve in the guage to hold pressure, otherwise all the cylinders would have quickly leaked down. So there may be some other issue.