W168 Emulsion in oil filler pipe

[lpgjag]

My sons W168 A140 is currently exhibiting a large amount of what appear to be yellow emulsified oil in the Oil filler pipe. We have had comments from Cylinder head gasket is required, to this is normal on the A Class, depending on where we take it. Do any member ahve expereience of this problem, and any advise on how to sure it from occurring? Thanks

 

[Bolide]

If the car does lots of short journeys I'd expect it to happen

Does the car lose water from the cooling system? Does it overheat? If so it may be a sign of pending CHG failure but the only way you're going to know for suer is to keep driving it and see what happens

If it does overheat, even once, stop and check the water level. If it's down I'd top it up & drive home to check for leaks

Nick Froome
www.w124.co.uk

 

[Nick1964]

I should check the quantity and colour of the engine oil on the dipstick and whether there's any oil in the coolant. It's also worth checking whether there's excessive water in the exhaust pipe and whether the coolant expansion taking is becoming pressurised. It could be poor quality oil, a blocked breather and short 'stop, start' journey's.

If it isn't exhibiting any of these problems and the temperature is running as normal, I would give it an oil and filter change and monitor it for a while.

 

[mattkh]

My sons W168 A140 is currently exhibiting a large amount of what appear to be yellow emulsified oil in the Oil filler pipe.

Hi
It is normal but scoop it up with a tablespoon, and see how long it takes to appear again.
A photo before you clean it up will be useful.
What is the mileage.
Is the car only used for short journeys?

 

[lpgjag]

Oil Filler

Tahnks to all for your various advice, the car is used daily for 2 x 42 mile journeys, so dont consider these to be short. One comment was inferior oil, the last service was at a non MB independent and it has 82000miles ont he clock. Will refill with good oil clean out and se what happens- presently there3 does not appea rto be any coolant leakage. Thanks again.

 

[Rizwan001]

How does it idle? Same as usual RPM? Any missing at all?
Change of filter with the oil can't hurt at any rate.
I would opt for K-Seal in the Rad, which will help put your mind at rest from overheating at any rate. I would flush or at least change the rad fluid first and introduce the K-Seal at this stage.
It does sound as if the CHG is weeping and the K-Seal could well save the hassle of replacing CHG if done sooner rather than later. Some gentle 'retorquing' wouldn't be a bad idea. Simply loosen each head bolt, one at a time, 60-70 degrees and tighten 90-100 degrees (approx). Start from the centre and pan out in order to distribute the pressure evenly and prevent distortion of CHG. Follow with a nice and easy run down the M-way.

 

[psmart]

Just to add to what mattkh and bolide have said. When I got my A140 and I checked it over, it had the same emulsion. I wiped it all out, changed the oil and in the 18months I owned the car, it never came back. At the time I suspected user error (putting screenwash into the oil filler) as its easily done.

 

[MB TECH WARRINGTON]

id say about 90% of a class we service have the symptoms you are talking about,
i believe it is due to the length of the filler neck which causes this,

if there is no smeg on the dipstick or in the coolant then i would not worry about it,


edit to add, a 42 mile journey does not mean that the revs ever exceed 2500rpm, if the car is given a good drive throughout the rev range every now and then it probably wont re-appear