Re: Fuel Leak From New Cap

[John Karasaki <johkar@teleport.com>]

At 07:30 PM 9/16/98 -0700, you wrote:
>Fuel is leaking out of my new fuel cap on my '87.5 coupe. What is the
>problem here? 
>Thanks,
>Wolff
>
Wolff,

I had a similar problem on our urq.  The tank breather hose that runs along
the top of the gas tank in the trunk had gotten pinched between the speaker
magnet (aftermarket speakers) and the tank top.

I didn't realize it until I was black flagged at a Porsche event because
the point man smelled gas.  It took me 2 months to figure out why the cap
leaked.  It only did it when the tank was near full and the ambient air
temperature was warm/hot.

This is what I discovered:  The breather hose allows the fluid and gas in
the tank to expand and contract.  If any of those hoses are blocked, the
pressure in the tank builds up until it bends the 2 tabs on the fuel cap.
The difference is so subtle that I had to measure it to see the difference.
 Major PITA and some clearcoat damage below the filler flap as well.

I replaced the stock Audi cap (again) with a $5 generic one after
installing a new breather hose that was longer and went around the magnet
instead of under it!

HTH.  Of course, it could also just be a defective cap rubber gasket, but I
suspect you replaced the cap because you had the same problem with the old
one.  BTDT.


Best Regards,

John Karasaki
Portland, OR