How often should you do a compression and leak down test?

I would do one and/or both test jus when ever I got a notion or if it went down on power at anytime.. never put enough hours on one ta suspect it wearin' out!

if your gonna "require" a leak down ya might as well take it to a mech. for general look at!.. would venture ta say 90% of folks sellin' and/or buyin' have no clue and/or tools ta do it.. a leak down can hurt ya if ya don't have any knowledge of "how to".. that motor has six (at a minimum) shots at of dottin' your eye... its not that "simple".. jus a comp is a different story...…. jmo.

When you purchase a used motor.

If you lose power.