Leak down /compression test

Compression tests are ok but the leak down test is the tell tale on the condition of the engine. Up to 25% leakage is still a solid engine. 25 to 40% is considered moderate and shows it has some wear that will need addressing in the near future. The good thing about the leak down is it will let you know where the issue is, air coming out the carb- leaking intake valve. air out the exhaust leaking exhaust valve and air out the dipstick would be worn rings or other piston issues.