Close
New head gasket leak down test results - are they okay?
1998 BMW 328i

New Head Gasket Leak down test results - are they okay?

(1998 BMW 328i)
I just put a new head gasket on my M52 engine and torqued it down. I thought just to be safe I would do a leak down test before I put the rest of the engine back together. The results may be fine or may be terrible, I'm hoping someone knows the truth of it.

So basically all my cylinders measured about 60 out of 90 PSI with the exception of cylinder 3 which seemed to seal almost perfectly.

I'm guessing that the engine needs to run a little, heat up and cool down a bit before the head gasket seals properly and therefore a leak down test before you run it for a while is meaningless. However, just in case there IS something horribly wrong I thought I would ask here as it could save me a lot of unnecessary "put together then take apart" time and effort.

So, could anyone confirm that I shouldn't really be concerned about this result?

Thanks,
Reg
Tags: bmw, 328i
1 answer & 2 comments
Popular Answer
on July 06, 2019

Are you referring to an actual LEAK DOWN TEST or a COMPRESSION TEST ?
Sign in to reply
on July 06, 2019

Add a tablespoon of light oil or transmission fluid to each cylinder - crank engine for a few seconds - then RE-TEST ..

Dry or wiped clean cylinder walls will drastically reduce compression!

Good luck to Ya!
on July 07, 2019

During an actual LEAK DOWN TEST - no pressure should be lost.

During a COMPRESSION TEST - each cylinder must have at least 100 psi for combustion to take place.

Add oil as suggested - crank engine a few seconds then TEST *COMPRESSION*..

Leak down testing requires above average diy auto repair skills while compression testing is much more straight forward.
General Diagnosis
$88 - $111 Learn More
on July 06, 2019

Are you referring to an actual LEAK DOWN TEST or a COMPRESSION TEST ?
Sign in to reply
on July 06, 2019

Add a tablespoon of light oil or transmission fluid to each cylinder - crank engine for a few seconds - then RE-TEST ..

Dry or wiped clean cylinder walls will drastically reduce compression!

Good luck to Ya!
on July 07, 2019

During an actual LEAK DOWN TEST - no pressure should be lost.

During a COMPRESSION TEST - each cylinder must have at least 100 psi for combustion to take place.

Add oil as suggested - crank engine a few seconds then TEST *COMPRESSION*..

Leak down testing requires above average diy auto repair skills while compression testing is much more straight forward.

Similar Questions

View answers to similar questions from RepairPal's community of auto experts and enthusiasts.
i was one block from my house when all of a sudden this noise came out of nowhere. i thought it was the air...
Carmax repair shop not available timely.