Date:         23 Jul 96 08:56:57 PDT
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         CARVER_JEFFREY@aphub.aerojetpd.com (Jeff Carver)
Subject:      Re: vapor lock type troubles

I had had a lot of miscellaneous trouble with my '80 until I stopped 
using ethanol enhanced gas from Beacon and ARCO.  The primary symptom 
was the same as clogged fuel filter.  Changing fuel filters solved 
the problem, temporarily.  Changing gas stations fixed it.
- Jeff '80 Westi


> Subject:       vapor lock type troubles

> I'm suffering from vapor lock type troubles in my '82/'84 vanagon on my way
> from Minnesota to California.  The symptoms are if I drive in the afternoon
> heat, it stutters and dies and then when I open the bleeder screw, lot of
> "air" (presumably vaporized gas) comes out of the bleeder.  If I drive in the
> evening after the sun has gone down, the problem never arises.  I've gotten a
> few other suggestions, but I'm not hopeful.
> 
> I dug this article out of the archives. It sounds more hopefule than other
> things and it rings true with something Joel Walker shared with me. If anyone
> has any clearer information about what is involved in this, I'd really
> appreciate email about it.   What does he mean by "header"?  Were they
> drilling a hole in the tank with gas still in it?
> 
> Any clues would be appreciated.

> 
> I too used the 10% ethanol blend (mostly ARCO) in my '84 without a problem 
> until:
> 
> A couple of years ago, while traveling in Idaho during an exceptionally hot 
> spell I started getting vapor lock type problems.  I took the car to a VW 
> dealer and was told that a lot of Vanagons were coming in with similar 
> problems just then, and that there was a free factory authorized fix.  I had 
> it done and no further problems.
> 
> The fix as described to me:  It seems that excess fuel not needed at the 
> engine is returned to the fuel pump at the tank.  The circuit is such that 
> in the header just below the tank the gas from the tank and the returned 
> fuel join and flow into the pump.  The vapor lock condition occurs when the 
> loop gets a vapor bubble in it that ends up in the pump.  The free fix was 
> to drill a second hole in the tank header leading to the tank.  This allows 
> any vapor bubbles in the fuel return path to rise through one tank path and 
> be replaced by gas through the other tank path.  The fix took 15 minutes at 
> the dealer, but I didn't see them do it.  I have never had the problem 
> again.
> 
> As a side note, I live in Phoenix where the summer temperatures are almost 
> indescribable.  The local gas suppliers do not use gasahol in the summer and 
> avoid the high vapor pressure problems.
> 
> Mike