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Leaking oil filler cap?

Hi all,

I have a slight problem with my US spec '98 A4 2.8 Quatro.

It seems that the oil pools around the oil filler cap and then will
drip down on to both the plastic covers and on to the head and exhaust
manifold.

I've replaced the oil filler cap once, but not the rubber seal that
fits under it. Is that rubber seal supposed to be sealed down?

Thanks.
--

Re: Leaking oil filler cap?

Paul Dhuse wrote:
> Hi all,
>
> I have a slight problem with my US spec '98 A4 2.8 Quatro.
>
> It seems that the oil pools around the oil filler cap and then will
> drip down on to both the plastic covers and on to the head and exhaust
> manifold.
>
> I've replaced the oil filler cap once, but not the rubber seal that
> fits under it. Is that rubber seal supposed to be sealed down?
>
> Thanks.
>
The seal is only held on by the tightened filler cap. You can try to
replace it again but it is probably a symptom of a bigger issue. You
might be getting excessive blow-by on the sides of the pistons due to
worn rings and high miles. If this is the case you will have the shoice
of rebuilding the engine or just living with the issue.

Re: Leaking oil filler cap?

On Tue, 03 Jun 2008 23:11:52 -0600, TonyJ <"tonyjnospam at nospam visi.com">
wrote:

>
>
>Paul Dhuse wrote:
>> Hi all,
>>
>> I have a slight problem with my US spec '98 A4 2.8 Quatro.
>>
>> It seems that the oil pools around the oil filler cap and then will
>> drip down on to both the plastic covers and on to the head and exhaust
>> manifold.
>>
>> I've replaced the oil filler cap once, but not the rubber seal that
>> fits under it. Is that rubber seal supposed to be sealed down?
>>
>> Thanks.
>>
>The seal is only held on by the tightened filler cap. You can try to
>replace it again but it is probably a symptom of a bigger issue. You
>might be getting excessive blow-by on the sides of the pistons due to
>worn rings and high miles. If this is the case you will have the shoice
>of rebuilding the engine or just living with the issue.

Interesting theory - but even assuming "blow by" would force oil out the
filler cap, wouldn't it be predicated by a defective PVC valve?