I will throw this out on Mud to confirm my interpretation of compression test results. Compression testing an engine this morning got this: Cyl 1 = 155 psi, cyl 2 = 20 psi, cyl 3 = 135 psi, cyl 4 = 140 psi. Dry test. Added a bit of oil to cylinder 2. compression went up to 40 psi. Added same amount more oil, got 80 psi. This would seem to indicate worn or failed rings or other problem in cylinder 2? Engine is not a Toyota.
Compression test results. (1 Viewer)
- Thread starter jgranthevagrant
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fjc-man
SILVER Star
A cylinder leakage test would confirm what’s leaking, can you hear it at the oil filler cap? Can you hear it at the tailpipe? Can you hear it with the throttle plate open? And then of course, the indicated percentage of leakage. With 20 to 40 psi compression, obviously the leakage amount will be unacceptable. But you’ll know where it’s leaking.
If your lucky it's just the head gasket. Leaking past rings, valves or cracked/broken parts is gonna cost you more. Good luck, I hope it's an easy fix.
fjc-man
SILVER Star
And as aztoyman is pointing out, with the radiator cap off during the leakage test, bubbles in the coolant. If it’s the head gasket - or a crack in the head.
- Thread starter
- #5
I don't have the tool for a cylinder leakage test, but might be worth getting one. Have been looking for a used long block but no luck so far. I might have to pull the engine apart myself. I have done lots of Toyota and Nissan motors, but this is a Subaru. Not good timing at xmas and I am most of the way through changing gears and adding an e-locker to my mini truck.
