Date: Tue, 4 May 2010 23:30:27 -0400
Reply-To: David Beierl <dbeierl@ATTGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Beierl <dbeierl@ATTGLOBAL.NET>
Subject: Re: Fwd: Gas tank and gas cap
In-Reply-To: <20100504214720.K670X.255591.imail@eastrmwml40>
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At 09:47 PM 5/4/2010, Dave Mcneely wrote:
>Looks like the receiver is pretty mucked up. Gasket appears
>stretched and maybe broken, and there appears to be rust or some
>other dirty looking material on the receiver. Maybe cleaning it
>would make a cap fit better, but perhaps it needs replaced.
Dear Annie,
The 'gasket' Dave is talking about is really the metal mounting
flange that the three mounting screws pull up against the inside of
the bodywork -- the sealing gasket is on the cap itself. The rust on
the sealing edge around nine to two o'clock may be a sealing issue
but not a cap-retention one. The visible tang inside the fitting at
about eight o'clock definitely appears bent as others have said. The
bright line extending upward from there is the edge of a pipe-end
reflecting. It's hard to tell from the photo angle -- I think it's
probably fine but might be worth checking to make sure it's actually
attached all around as it should be. Again, a pressure-integrity issue.
I'd suggest to clean up the rust at the rim, and otherwise if your
cap stays on and holds pressure (your next inspection may tell you
that) to not worry further about it.
Do check the +10v at the back of the fuel and/or temp gauges -- if
it's low both gauges will read low. If it's a little low your temp
light will also be blinking, but I don't know what happens there if
it's low enough to do as you describe. It's difficult to get to the
fuel gauge sender (although small hands and "eyes at the tip of your
fingers" help), but I can tell you at least how to test the gauge
calibration -- if a PO adjusted the gauge without knowing that the
test values in Bentley are not in ohms, the gauge could be way
off. You might want to pmail me to talk in a bit more detail about
gauge behavior.
And I have a heretical opinion about running the fuel out to check
capacity -- the book says don't run the pump dry, and indeed you
shouldn't as it's lubricated by the fuel passing through it. But
it's my belief, borne out empirically in several vehicles including
the Vanagon, that running it dry deliberately, expecting it and being
ready to shut down the engine at the first sign of stumble, will have
no ill effects if not done regularly, and I routinely do it with
every new vehicle because I want to know what the gauge *actually*
says when it means empty. That's easy to do so long as you stay
within fill-up range of whatever amount of spare fuel you're carrying
for test purposes. Carrying spare fuel is of course a hazard in a
collision and can have very severe consequences, but I personally
deem it an acceptable risk (to me) for the purpose. Ask me again
after I've been burnt to a crisp. Knowing the empty point and how
much fuel went in after you ran out, you may find a gas station with
enough leisure to allow you to fill it a gallon at a time with a
couple-minute wait between each gallon, and plot the gauge readings
for each gallon fill.
This semi-obsession with gauge correction curves etc may be part of
my (half) German background. Or engineering inclinations. Or
deep-seated mental illness... <g> But I *do* tend to know how much
fuel is actually in the tank. Maybe it comes from cruising in sailboats.
Yours,
David
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