oil cap query

desh Wolfsburg Wizard

463 posts · joined Jan 2009 · 30 Aug 2009, 4:54 pm

#732463

Hi

I have been using my Beetle a bit more lately to give it some use and I notice under the oil cap it looks like this:

Seems to be some sort of white / creamy substance forming, if I clean it off every time I use it, it isn't so bad.

What is this?

Why is it there?

Someone had advised me it may be because I am not warming it up enough and condensation forming under the oil cap,

It is not on the dipstick at all.

Thoughts?

thank you.

--------------------------
Kind Regards
Des

bushed Wolfsburg Elder

3,541 posts · joined Dec 2006 · 30 Aug 2009, 6:30 pm

#732480

condensation takes place with water so maybe some got in somehow
change the oil and some vw's dont like bp longlife so make it good oil

want any vw bits old but like me, Made in Germany!!!

Joel Now containing 100\% E-Wang

9,368 posts · joined Feb 2006 · 30 Aug 2009, 7:02 pm

#732490

as bushed said its just condensation in the oil

thats what happens when cars do short city trips
they dont get hot enough to boil the moisture out of the oil

desh Wolfsburg Wizard

463 posts · joined Jan 2009 · 30 Aug 2009, 7:04 pm

#732491

Joel wrote:as bushed said its just condensation in the oil

thats what happens when cars do short city trips
they dont get hot enough to boil the moisture out of the oil

Dumb question, but how does moisture get in there?

My car lives in a shed.

Thanks both of you, will get an oil change done and keep an eye on it.

thank you

--------------------------
Kind Regards
Des

bushed Wolfsburg Elder

3,541 posts · joined Dec 2006 · 30 Aug 2009, 7:09 pm

#732494

RAIN
PUDDLES
FLOODED CREEKS?...water finds its own way..check the filler pipe is on tight
CHEAP OIL
HAVE U GOT A BREATHER PIPE TO THE AIRFILTER?
THAT SUCKS OUT SOME CONDENSATION

want any vw bits old but like me, Made in Germany!!!

desh Wolfsburg Wizard

463 posts · joined Jan 2009 · 30 Aug 2009, 7:14 pm

#732496

bushed wrote:RAIN
PUDDLES
FLOODED CREEKS?...water finds its own way..check the filler pipe is on tight
CHEAP OIL
HAVE U GOT A BREATHER PIPE TO THE AIRFILTER?
THAT SUCKS OUT SOME CONDENSATION

Maybe these are obvious questions to others, but does rain get in through the vents above the engine lid?

I assume the air breather pipe is the big grey one there that is going down into the engine near the oil cap?

Thanks for your help mate

--------------------------
Kind Regards
Des

grumble Son of Jim - Creator of Good

2,672 posts · joined Jun 2008 · 30 Aug 2009, 9:10 pm

#732536

Yes it is condensation we found a few oils more prone to this condensation quite a few years ago,one of the major oil companies whose rep said it didn't happen was one of the most prevalent.The crankcase is vented to the atmosphere and if it doesn't run at operating temp this makes it more prone to this. I use Valvoline or Caltex oils and find we have very little problem. I would suggest a good quality oil from a major manufacturer such as either of these and not a cheaper supermarket/cut price auto store.( I do not have any connection to either of these oil companies but have used both regularly)

desh Wolfsburg Wizard

463 posts · joined Jan 2009 · 30 Aug 2009, 9:28 pm

#732549

Ok thanks, I have Castrol in there at the moment, will get an oil change done this week and see what happens,

thanks for the help.

--------------------------
Kind Regards
Des

cesiumfrog Seriously Crusin Dubber

161 posts · joined Apr 2005 · 30 Aug 2009, 9:59 pm

#732555

saponification.....soap!
when moisture laden air reacts with oil and some metals or ions and heat you get this deposit via chemical process callled saponification...used to make soap and some greases can be obtained by this process or altered to give them specific properties.
cold weather..short runs..need to get your engine hotter for longer.

VWCOOL 23 Windows of Awesome

5,158 posts · joined Jun 2003 · 30 Aug 2009, 10:30 pm

#732562

For every litre of petrol burnt,your engine prouces a litre of water (I think!). Some of that water finds its way to the oil. No stress, a freeway run once a month steams it out of the oil

Pay your debts, CxxT

matberry Moderator Go hard or go home

8,114 posts · joined Mar 2006 · 30 Aug 2009, 10:33 pm

#732563

The moisture comes from the air not the oil, but if the engine doesn't see long enough trips the moisture gathers at the cap and is not burnt away. Every time the engine cools down, as the temp drops, the air contracts so cool atmosphereic air enters the engine and it brings with it some h2o to add to the cap.

Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
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