E30 Zone

Hi,
Just done a comp test on my warm m20b25, the results were the same across all cylinders but seem quite high compared to what I have read elsewhere on t'interweb.

14 bar + on all cylinders (>200 PSI)

Thanks in advance

They do indeed sound very high; normal pressures are around 175-190 psi.

Are you sure the gauge is calibrated, and which engine block do you have - 25 6E or 25 6K?

gauge is brand new and will confirm block shortly.

How can you have "too" much compression?,I thought more the better?

That's a genuine question not a smart Alec remark btw

well i have some quite bad oil leakage issues so high compression may be responsible.

Basically enough pressure to blow the filler cap off! Both oil breathers are clear so not sure where, why or how it is leaking oil but if I drive over 2k rpm it proper spooges oil from somewhere around the back of the block. Comp test was first point of call.

That's got nothing to do with compression. The filler cap blowing off is crank case pressure. It's interesting that you have too much compression as well as ccp.

I know this sounds stupid but how much oil is in the engine?

how much oil? Well the dip stick is a good level and i put in the "correct" amount...

Only reason I ask is because overfill could cause a high amount of crank case pressure. Have you tried running the engine with the filler cap off?

Engine runs fine and oil goes everywhere its supposed to. None of the pathways are blocked and new oil is still nice and golden.
Only other thing I have changed is I rotated the oil filter housing to allow for tubular manifold, and removed the oil cooler. From research I understood that both of these are completely fine to do... Unless I maybe have restricted the oil channel into the filter housing somehow

What grade of engine oil did you use? It may be worth trying a thicker one - 20W50 was used back in the day, when these engines first came out.

Lighter grade modern stuff may be too thin and be the cause of the leakage on an older engine.

Im on 10w40 semi-synth at the moment and that is what I have used since I owned the car.
I replaced the headgasket recently and did a complete top end rebuild and problems have only started since then.
I think oil is leaking from the rear crank seal area, but still no real clue as to the cause.

Check the oil pressure relief valve is functioning properly.

http://e30.bmwdiy.info/oil-leak/