New motor. Bad cranking compression
#1
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One cylinder is at 220. Adjacent cylinder is at 120!! 5 of 8 have abnormal psi. Leakdown showed an 80% loss.
Everything looks brand new. Rings look good. Cylinders look good. Heads/valves are fine. Next thing to check i guess is cylinder distortion.
Any ideas?
Everything looks brand new. Rings look good. Cylinders look good. Heads/valves are fine. Next thing to check i guess is cylinder distortion.
Any ideas?
#2
TECH Resident
iTrader: (4)
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If the rings and valves are ok, then it has to be a head gasket. if your cylinders are distorted, then your rings will leak. You can't do a leak down on a engine unless it has been run to break in the rings. Did you do your compression check with the throttle wide open? This will cause abnormal psi if you don't.
#6
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Were the cylinders honed by machining or hand held drill? What is the ring end gap? Cylinders could be out of round. If it was the head gaskets I believe you would have 0 pressure in the effected cylinders.