Yellow sludge on oil dip stick...

Soldato
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Was checking the oil in my (very old) BMW and noticed some yellow sludge on the dip stick.

A bit of googling suggests this could be very bad (cracked head gasket) or just because I only drive it short distances (3 miles x 4 times a day).

It also struggled to start today (having not driven it since Thursday) and required a lot of force to get it into gear.

I know nothing about cars and dont drive much so does anyone have any pointers on the above? :)
 
It was dark but the sludge was at the very bottom and just above the lever indicator bit - the but in the middle did look normal.
 
What engine?

BMW 6 cylinder engines do this in cold weather if you do very short trips. Every winter my 530i does this, every summer or after a proper trip it goes away.

It can indicate head gasket problems because it occurs when water mixes with the oil - but water mixes with oil when condensation exists and isn't evaporated by the engine remaining at operating temperature long enough, as well.
 
I think its condensation from what you have said. The engine usually over heats and oil looks like mayo when the gasket fails.

Defiantly worth keeping an eye on though.
 
I've noticed this in my Audi this winter. Just keep checking the oil and make sure your temp gauge doesn't start creeping up.

Also may be worth checking your coolant for oil too. If it's clear you're most likely ok.
 
You shouldn't diagnose HGF without other symptoms too. Keep an aye out for rough running or chugging when cold, a steamy exhaust and most importantly; oil or coolant loss.

I think it's down to your short journeys.
 
If the coolant level hasnt dropped it isnt a failed headgasket and we are currently in the perfect weather for condensation to get into the engine.
 
As above, no need to jump straight to headgasket failure. Its just condensation, engines have breather which allow moisture in the engine and a bi-product of combustion is a certain amount of water. Unless the coolant is canstantly dropping i would worry about it.
 
Is it true that taking it out for a good few hours drive can clear it up after the first time, or does it need a few runs to sort out?
 
If you are losing coolant as well - Then it could be head gasket.

...Has the car overhearted recently?

Also check the coolant tank - See if there is any signs of mayo etc...


'get in into gear' - is it manual or auto?
 
If you are losing coolant as well - Then it could be head gasket.

...Has the car overhearted recently?

Also check the coolant tank - See if there is any signs of mayo etc...


'get in into gear' - is it manual or auto?

It never even gets out of the blue section of the temp guage!!

I need to check the coolant however the car was fine today.

Its a manual.
 
if its just a bit its not to worry about in this weather. in an engine oil pressure is higher than the water pressure so if the two are mixing you will (typically) find oil in the water rather than the other way round.
 
Usually from the cold/condensation as people have said, personally if it were my car I would change the oil as a matter of course as you dont want that slopping about your engine as your lubrication efficiency wont be as good.
 
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