Date:         Wed, 18 Dec 96 13:41:17 CST
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Joel Walker <JWALKER@ua1vm.ua.edu>
Subject:      Re: need help with coolant leak

On Wed, 18 Dec 1996 10:40:19 -0600 you said:
>THis description isn't very precise, but I hope someon knows what I'm
>talking about.  ANyway, there's coolant leaking at the point where this
>piece meets the cylinder head.  Do I need to replace this piece, or is
>there a gasket between this piece and the head?  I've been told that this
>piece can break (is it plastic?), but as I said, I don't really know what
>to call it.  I think somethinge may have happened in the cold yesterday
>to cause this problem.  By the way, it's an '87.

yup. that's the infamous Plastic Flange that we've talked about. yes, you
need to replace the flange (the old one is plastic, and the new one is
metal).
BUT!  there is an o-ring under the flange. and the new one does NOT have
a place to "hold" the o-ring. :(  i had to use some NAPA generic gasket
material to get it to seal:

NAPA Thermostats    Part No. STM-1
     Adhesive Backed heady duty Gasket Material
     for proper sealing of
     * thermostats               * carburetors
     * water pumps               * fuel pumps
     and for general household use <sic!!>
     self adherinng * no gasket cement needed
     for all gasket uses involving oils, fuels and water
       temperatures up to 300 degrees F.
          a product of Standard-Thomson Corporation
          Waltham, MA. USA

anyway, it works. clean the antifreeze off the engine side (you'll loose
a LOT of coolant when you remove the flange. be prepared. but when you
refill the coolant tank, it refills the engine and bleeding the radiator
bleed screw produced no air (on my 88)). "a lot" being about the whole
coolant tank's worth. so you'll need at least a gallon of 50-50 mix to
refill it. and make SURE you get it sealed (with a good gasket) BEFORE
you refill it ... my first attempts with the dealer-supplied o-ring ("we
don't show any other 'new gasket'") didn't seal and i had to lose all that
coolant again when i removed the new flange to reseal it. :(
joel

here's the part number info:

Import Service, March '90  Vol3, No 3
Vanagon coolant leakage

"A damaged plastic coolant return flange located at the rear of the
right cylinder head can cause coolant leakage on 86-88 models.  The
plastic flange is close to the engine's drive belts and can be
damaged by a loose or broken belt.  Engine overheating can also warp
the sealing surface of the flange, causing coolant leakage and more
overheating.

To correct (or avoid) these problems, replace the damaged plastic
flange with a metal coolant return flange, P/N 025 121 160 D, and
gasket P/N N 901 685 01."

>From: "Dan Houg" <fairwind@northernnet.com>