What are the reasons that this happens, im not sure if its high crank case pressure (i did clean out that breather at the back of the engine and it hasnt made a difference) or high oil pressure. its done 170k now so could that be the rings?
Thanks!
mine did this last year and it was rings. do a compresion test and you will find out if one is lower than the rest.
anyone know what sort of miles the rings start going at?
Ah right, what should i expect from a compression test if they are blowing?
Anything 9 Bar or below is cause for concern.
OK. well it wasnt the breather so did a compression test yesterday on a cold engine and resuts where!
1. 120psi
2. 150
3. 140
4. 150 (aproximate values dont remember specific)
so did no.1 again and it went to 150psi. what does that say about the rings? anything else that would cause high crank case pressure?
Thanks!
valve in the oil pump being stuck... this happened to the hayes i think
that caused excessive oil pressure yeah but it made the oil light and buzzer go mental. Try a compression test with a hot engine. Plus are you sure the breather isn't blocked still? There's two parts, the plastic valve and the actual metal breather pod on the engine block. Plus check the condition of the rubber pipes, if they are perished and have gone all soft they might be closing themselves up.
Quote from: hayesey on January 12, 2010, 11:08:54 AM
that caused excessive oil pressure yeah but it made the oil light and buzzer go mental. Try a compression test with a hot engine. Plus are you sure the breather isn't blocked still? There's two parts, the plastic valve and the actual metal breather pod on the engine block. Plus check the condition of the rubber pipes, if they are perished and have gone all soft they might be closing themselves up.
Took off the breather pod and have it a blast on an airline + carb cleaner. No oil buzzer or light at all, apart from on some loooong slip road where the oil moves across in the sump! had new breather pipe + boost return pipes this year too. plastice valve got some carb cleaner and airline too
Are you seeing a lot of pressure/fumes when you take of the oil filler cap? I was thinking along the lines of worn valve stems and seals.
not that i have notice'd will check again tomorrow though. always just seemed fine whenever i have checked it
it might be your head gasket is gone across into an oil port.
Quote from: grayg40 on January 13, 2010, 10:06:39 AM
it might be your head gasket is gone across into an oil port.
There is a weepy corner on the left hand side, would this say anything?
only the alternator if it gets clogged up with oil.
I've often thought this is related the block flex- always the same corner (engine mount/charger side) irrespecitve of type of gasket, decked block, skimmed head etc.
As Pete says- only downside is the alternator getting smothered in oil- plus side is the underneath of your car will never rust!
Easiest way to work out if your rings are shot is to do a compression test then do it again but this time put a few sperts from an oil can in the cylinder before you screw in the compression tester if the readings are alot higher you can pretty much guarantee its rings or bore wear!
Send that to the as yet un-started top tips corner.
Yeah.
Plus, as someone has alreads stated, if you take off the oil filler cap when the engines running you shouldnt get much blowing out of it. If its breathing like hell then its probably the rings.
thats not the same on all engines though, most bmw engines wont even run without the oil cap on.
Usually to do with breather systems that rely on a negative crankcase pressure- if managed by the ECU they get the hump quite easily.