Date: Mon, 5 Oct 1998 11:34:26 -0600
Reply-To: Jonathan Nowaczek <Jonathan.Nowaczek@NETALLIANCE.NET>
Sender: Vanagon Mailing List <Vanagon@vanagon.com>
From: Jonathan Nowaczek <Jonathan.Nowaczek@NETALLIANCE.NET>
Subject: Re: Gas tank leaks (LONG)
Content-type: TEXT/PLAIN; charset=US-ASCII
Sorry to hear that your vehicle has the DISEASE; my '82 Westfalia is on
it's THIRD gas tank. IMHO, the gas tank is one of the major weak spots in
the design of these vehicles. Maybe I can save you some of the hassles I
experienced.
First, the job of changing out the tank is covered in a procedure
somewhere in the Archives. If you can't find it, I have a paper copy
somewhere. It's a job that's not at all technically difficult, but is a
filthy, nasty job. For example, You can drain all but about the last
half-gallon of gas from the tank; this last bit is sure to spill all over
you as you get the tank out. Remember: Gasoline burns fast and well.
Don't take any chances - Disconnect the battery ground strap, keep all
sources of ignition away, and have an assistant nearby with an
appropriately sized and rated fire extinguisher.
As you may have already found, new tanks from the VW dealer are incredibly
expensive (~$495 or MORE). Also, the new tanks are available ONLY with
the 1 7/8" filler neck, which may require you to purchase additional parts
if your vehicle was originally equipped with the 2 1/2" filler pipe.
There were several design changes over the years - same basic tank design
from '80-'91, but two different filler pipes, and a couple minor
variations on filler neck venting.
Replacing ALL of the seals (there are 4: three for vents, one for filler
neck) is a MUST. While the tank is out, it's also a good opportunity to
see if any of the vent hoses or clamps need replacement due to cracking,
corrosion, etc. It's an amazingly complicated design. It's also an
excellent time to replace the fuel sender, if yours has been giving any
trouble. BE CAREFUL - this is also a prime spot for leaks to develop, and
you won't find out until you've got the whole thing back in the vehicle
with a tank full of gas. The senders are plastic, and can easily be
cracked with the force it takes to get it to seat properly. Liberal
graphite lubricant helps here. VW specs a special tool for
removing/installing the sender; you can make a makeshift one out of
plastic or wood - make sure you use something WEAKER than the plastic of
the sender. Remember to ALWAYS replace the o-ring seal any time the
sender is removed.
BEWARE of rebuilt/remanufactured tanks. There are internal pipes leading
to a central sump (one for feed to fuel pump, one return from engine), and
these can easily be plugged with the materials that are commonly used to
seal the tank interiors. There also seems to be huge variability in
performance of the sealing products. I purchased one tank that was
rebuilt with a two year warranty; was coated inside with a reddish rubbery
compound, outside with a black plastic resin (called '414' I think?).
External compound separates from the metal, internal material peels out.
Started leaking one month after the warranty was out...
My latest experiment is with an outfit called Gas Tank Re-Nu. Their price
was reasonable; they're nationwide, and they offer a _lifetime_ warranty.
Their process looks good, using polymer compounds developed by/for the
military that are baked at 400 degrees to cure. Resulting rebuilt tank
really looks durable. Just put one of these in my vehicle this summer -
I'll update the list on how it performs.
Lastly: Do yourself a favor and put some anti-seize compound on the bolts
that hold the tank carrier rails to the frame. Chances are you WILL do
this AGAIN, and you don't want to have to struggle with those
frozen/rusted bolts again.
Best of luck.
- Jon
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