rsguy

need some help regarding compression readings.

my engine compression rate ( cr ) of my engine is 7.4:1 im not sure what compression psi readings i should get getting with that rate. can anyone tell me what psi readings i should be getting please. and if my test psi readings look ok.

i done a compression test today and got these readings .

dry test

cylinder 1 - 130 psi
cylinder 2 - 130 psi
cylinder 3 - 130 psi
cylinder 4 - 130 psi

wet test

cylinder 1 - 140 psi
cylinder 2 - 135 psi
cylinder 3 - 130 psi
cylinder 4 - 135 psi


thanks

stevieturbo

The fact they are all very close together is largely all that matters. The engine can be deemed fairly healthy

rsguy

ok thanks steve.

i thought possible worn rings or bores as my engine is thowing out white/grey smoke when warm and smells of oil.

done a leak down test and its saying cylinder leakage moderate 65% on all cylinders.

also tryed just useing 100psi of air i hear the air escaping out of the engine dipstick & oil cap.

this would suggest Rings/cylinder seal.

however the compression reading on all cylinders do look all close together so i think maybe the rings are ok.

im thinking maybe valve stem seals. however im not sure if worn valve stem seals would cause blowby in the crankcase.

stevieturbo

As I said, only deemed healthy. You never mentioned any symptoms of a problem like you just did now.
A compression test is just that. It won't always tell you of a ring problem leading to oil use or smoking.

Leakdown of 65% isn't great tho.

Assuming all tests conducted correctly etc