Alright so i was looking around in my engine bay today and took off my oil fill cap and there was milky oil on the cap and around the edge it looked as if the oil had water in it and i thought i had a head gasket leak. I drained my oil and its perfectly clean other than being a little used (about 2000 miles).

What could this be? The car did start to overheat lastnight but i shut it off and let it cool down than finished the 5 minute drive home. Could this have any signs of what is wrong or did some moisture just get under the cap? The weather has been in the mid 20's for the past few nights and not much warmer during the days.

do you do alot of stop and go city driving? that style of driving has been known to cause the milky oil cap issues.

where is york compared to bethlehem? i'm there for my good buddy's wedding....

solidfied condensation causes the 'white stuff' on the oil cap during the colder seasons. Perfectly normal.

cos m3/4

yea it could be nothing -- clean it off - wait a while and recheck

phew, thats good to hear, i was worried i might have to replace a head gasket which i definatly didnt feel like doing. Thanks guys for your help.

do you do alot of stop and go city driving? that style of driving has been known to cause the milky oil cap issues.

where is york compared to bethlehem? i'm there for my good buddy's wedding....


Im gonna say 2 hours or so but dont hold me to that, it could be anywhere from 30 minutes to 4 hours. But Bethlehem seems to ring a bell at around 2 hours away.

,,,The car did start to overheat lastnight but i shut it off and let it cool down than finished the 5 minute drive home. Could this have any signs of what is wrong or did some moisture just get under the cap? The weather has been in the mid 20's for the past few nights and not much warmer during the days.

Might be condensation but with the above I wouldnt count on it.
If its overheating due to low coolant I would be finding out where the coolant went.

Coolant is fine though i had checked it, when i was looking at the oil to see if there was anything in the coolant but it was fine and full. The overheating thing im really confused about because i dont know what caused it.

Im gonna say 2 hours or so but dont hold me to that, it could be anywhere from 30 minutes to 4 hours. But Bethlehem seems to ring a bell at around 2 hours away.

lol, I think you can get to anywhere in PA in 4 hours can't you? I got back into madtown today (man it always feels good to get home)

It's entirely possible the overheating and presence of condensation on the oil fill cap are not related. It's not unusual to find a little bit of foam on the cap. I recommend diagnosing the overheating first.

Alright i planned on looking at the overheating hoping its the thermostat again but the foam scared me a little bit.

yeah definetly diagnose the overheating problem first.

i don't have foam but oil comes out of the cap when engine is running. Is that normal? Is that are suppose to be under pressure?

Hello fellow BMW enthousiasts. I concur with the wider audience regarding the milky cap, as long as main oil is ok dismiss, however cracked heads do unfortunately occur, mainly to my experience they are more with the M42 4 cyl. and the newer M54 6 series, although I have seen a few M50 and M52 heads crack. usually after an overheating. My M42 head let go and had one of the cyl. start filling with coolant after shut down....I was not concerned for at the time had already planned the M50 engine swap. Anyway there are many suggestions and the most obvious that come to mind and if it where my car I would address the following right away:

1st the dreaded Radiator neck top hose connection, might not be leaking but should check anytime coolant system is being worked on, the slightest overstress after removal and re installing upper hose can cause unplanned cracking at inoportue time. If recently replaced then discard this concern, cause - according to BMW at time I was working with the term used was radiator failure due to imbrittlement.
2nd Anyway the most common failure I see are the water pumps - plastic impeller cracks and water pump simply quits working. Fairly easy to check, just remove water pump, these are very easy to switch out.
3rd Also the thermostat can break closing off flow. Depending on climate and driving condition this may be a good time to swap out with cooler one if so desired, I went with one from a 1979 733. 80 cel, and E36 318ti Rad. temp switch (also 80c) now my temp runs just over a 1/3 to below half under spirited driving.

4rth Checking the head, besides removing the V Cover and looking for fresh signs of milkshake (most certainly cracked) If you have access to a gas analizer or a mechanic who "knows how to read it for other diagnoses" then this is the best tool, simply run car to just warm , remove cap at reservior (not too hot as to be safety & hazard free), catch it on warm up, not after you just finished the indy 500 pit stop, anyway "sniffing" the gas just above the coolant will yeild the answer. If the sensor peggs with high hydrocarbons you are done time for a new head/ and or head gasket. Note, if the sensor dips into the fluid, then the gas anailizer is done, Coolant is like sionide to the machine.

Water pumps are like wine, everone has a preference in taste, as for me I prefer the factory new ones, they are made of bakalight now, not soft plastic and I have had no problems, change them out every 50-70K miles or so. I don't like the metal or cast impellers for it adds too much weight against the shaft bearing and when water pump lets go it usually trears everything up in the soft aluminum front cover housing. Again though personal preference.

One last thought. The E36 had a new design incorporated into the instrument cluster regarding temp. the middle of the gauge really isn't middle or accurate, but rather a default for a moderately wide fluxuation in temp changes. Ever notice how it once starting to warm jumps right to middle? I say this; if it reflects a over heat.or warm........then man jump on it now..........you are just begging damage by driving it.......

Those racers out there know what I am refering to as the temp guages are one of the first items along with better Oil temp gauges to be addressed.

Hope this helps.

TTFN,

Brice

.......so i appreciate the help but that was 2 and half years ago.

safe to assume things were fine then ? :)

yeppers, its even a little quicker now.......

i don't have foam but oil comes out of the cap when engine is running. Is that normal? Is that are suppose to be under pressure?No and no.