mayonnaise on dipstick (BMW E46)

tc20

Hi all,

i have a loan of my b-i-l's car for a week or so while he's on holidays, and mine's off the road. Its a 03 318 (i think that makes it an E46) and being curious, had a look under the bonnet. Granted there's not much to see, but i checked the oil to see if she's ok. Firstly, the dipstick seemed a bit difficult to pull out and it actually looks corroded near the top of the stick. The stick doesn't easily glide back in its housing either.
secondly, and more importantly, there is a mayonnaise like gunk deposit on the business end of the stick - i checked under the filler cap, and all looks sweet there, the mayo on appears on the stick.

He doesn't have the car all that long, and i believe it was serviced recently. Car seems to drive ok, no smoke orany real hesitancy.
Has anyone any ideas as to what might be causing the gunk?

jaybee747

Think i read about this before, something to do with the Gasket going or gone and the water mixing with the oil.

peasant

The least sinister option is frothy oil from condensation mixed with oil. The condensation would be due to the car only getting driven on short journeys and never really reaching optimum temperature for long enough to burn it off.

rebel.ranter

The reason why the dip stick was difficult to remove:
BMW oil systems operate in a vacuum, if you leave the dip stick out or loose or the oil cap off or loose the car will idle like a pig. There should be a rubber bit on the top of the dip stick to maintain the seal.This rubber seal can stick if not checked often, I find if you twist it before you remove it then it will come out much easier.

On the mayonaise:
wipe it off & if the car is getting regular use with decent distances driven then wipe off the residue & monitor it over the next while. As peasant says it could just be a build up of condensation in the engine due to the short usage times.

tc20

thanks for the replies lads.

@ rebel.ranter - both the cap & dipstick were securely in position before i attempted to remove them. I'll double check for the rubber seal in the morning. I did actually try both methods of pulling the stick, straight pull the first time, and with an added twist the second time either way it didn't pull freely, and as i said, it wasn't the easiest to get fully back in either.

@ peasant - its possible, as in the last couple of days the car has only had short runs (couple of miles each way). The cars regular drive is a 1 hour mixed commute, so i'll keep an eye on it over the next few days.

shamrock105

Just on the mayonnaise gunk bit. Had a similar experience in my Polo recently. Dropped into Halfords on the way home and the chap had a look at it. Said it was nothing to worry about. Can be either the result of infrequent use and condensation accumulating or (in my case most likely) the type of oil that was used. He mentioned that some type of Castrol oil tended to leave this mark from time to time. It was literally just the tip of the end of the dipstick. Under the filler cap was clear of white residue and there was no leaking around the head gasket. The coolant was still as pink as it should be and the oil temp in the car has been normal. If your coolant froths up, changes colour or the oil temp starts to move upward then start being concerned. Otherwise just monitor and dont worry about it for the moment.

corktina

oh well, if HALFORDS say its OK then it must be .....:rolleyes:

Get a mechanic to look at it if you are worried, they are an expensive engine to repair/replace

Marty McFly

Well i wouldnt say it the head gasket now im no expert but i had a car were the head gaslet went and the oiil was more of a muddy colour, like a light brown form the water mixing with the oil.

To be on the safe side jsut get it checked out.

Pkiernan

I'd change the oil and filter, and keep an eye on it for a while.

pa990

and stay away from halford's, unless you want an air freshner or some twinkly lights