Do a valve adjustment and a leakdown test. The results of a leakdown will help tell where the compression is being lost by where the air escapes, then you will know if the rings are ok and just the valves are leaking.

If the rings leak you could try a solvent soak on them, run it hard for an extended period and re-do the test.

Diagnosing is particularly important when funds are limited, it saves doing unnecessary repairs.

Good luck!!!

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