White-coloured deposit in oil-filler cap W202

[Alex Argent]

Hi Benzers
During a routine 'walk round' check earlier this morning, I removed the oil-filler cap (for nothing other than idle curiosity - it didn't need topping-up according to the dash 'low/ok/high' system) and ALARM.....inside the top of the filler cap and around the top of the filler neck, I noticed a white/grey sticky deposit. This only the second time I have removed the cap since owning the car (approx. 7k miles) and I remember the first time was some months ago when I filled up with about half a litre of Castrol Magnatec 10/40W. However that was during the evening and it was fairly dark so I didn't really look too closely at the cap.
Now firstly, the car has been running fine (although it is due an 'A' service in 1400 miles), and secondly, I have never had to replenish any coolant, and that still looks as clean as new on checking. Lastly, after I topped up previously, the oil level 'on-board' system was showing 'High', but rather than draining any off (it was only half a litre as I stated), I just ignored it. The Stealership service history shows Magnatec was used on all previous services.
I'm obviously worried that a head gasket may have blown or some other catastrophe, however could this be just oil emulsification? Am I worrying unnecessarily? Please some nice person, put my mind at ease!
Look forward to your comments.
Regards,
Alex

 

[Ian B Walker]

Alex, I would check your oil, if it is creamy then I would suggest that your head gasket has gone, but as you have said your water level is ok I doubt that it has. It may just be the result of condensation in the engine that has caused your worries. Me? I would change the oil now, but that is me. Others here will know better than I?

 

[Paul]

Take the car on a good long run of at least hour, this will burn off any condensation in the engine. Then when you re check the filler cap you will prob' find it's all ok.

This problem is very common when the car is used regulary for less than 20 min's a trip.

 

[esox]

Do you do lots of short journeys-this will tend to form the "mayonaise"that you describe if the engine does not reach a high enough temp to burn condensation off.

 

[Alex Argent]

Hi Guys
Thanx for the prompt replies. I definitely now feel a lot less concerned than I did two hours ago!
As a matter of fact, I have been taking the Missus into work and collecting her again in the afternoons since the beginning of December. This involves two round trips per day of about 1 mile each, so what Esox and Paul have said seem to sum up the problem, or at least I hope it is just condensation. As the coolant has never required topping-up (and as it is as clear as a bell), it does seem logical that it's not a head gasket blown. Having said that, I think I'll take Ian's advice and do an oil change immediately, or bring the service forward by a month or so.
I'm now thinking out loudly to myself - on the assumption that these short daily journeys are going to continue for a while (come on guys, one of us has to go to work to pay for the tax, insurance, fuel,.....), it may pay me to do an oil change between stealership services (i.e. approx. every 6-7,000 miles). I'm sure that would be worth the £40 of Magnatec and £5 or so for the filter every six months.
So well done to all, you HAVE put my mind at ease so 'ere.......ave a nana! :bannana:
Best regards
Alex

 

[andy_k]

As others have said, quite normal - particularly in the winter. The oil filler cap is the high point of the system and also one of the "coldest" so it's natural that any condensation would form there. To test how much of this gunk has formed, run your finger around the underside of the lip (cam cover) you will probably find that any residue there is perfectly clean.

An oil change won't really help that much (but it won't do any harm) as the same thing will probably happen within a few days

Andy

 

[Robbo]

Alex,

Like the others have said, dont worry. Its completely normal for the V6 engines to do this in cold weather. The oil filler cap does not get quite as warm as the rest of the engine and in cold weather, condensation will collect there. It will go away when the weather gets warmer.

 

[esox]

I have been taking the Missus into work and collecting her again in the afternoons since the beginning of December. This involves two round trips per day of about 1 mile each,it may pay me to do an oil change between stealership services (i.e. approx. every 6-7,000 miles). I'm sure that would be worth the £40 of Magnatec and £5 or so for the filter every six months.
Best regards
Alex

You drive your missus 1 mile........,save the £45 and buy her a pushbike!

 

[Robbo]

Oh and another thing, I wouldnt use semi synth in this engine. With the FSS extended service intervals it has been known for sludging problems to develop. IMHO, only fully synthetic oil should be used.

 

[Alex Argent]

You drive your missus 1 mile........,save the £45 and buy her a pushbike!

I know, I know.......I put it to her gently this afternoon that she's knackering the car. All I got was, well........if looks could kill! Maybe I'll pluck up the courage again when the sun comes out. On the other hand, you could always have a few words with...................... er perhaps not, let's wait for the warmer weather!

Again chaps, thanks for the excellent responses and for allowing me to sleep a bit better tonight. I (and no doubt countless others) owe a lot to this wonderful forum and to the many people who give up some of their free time to helping others out! Long may it continue :bannana:

Alex

 

[guydewdney]

or buy an old banger / moped?