Date: Wed, 11 Oct 2000 10:54:03 -0300
Reply-To: Tim Smith <smitht@UNB.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tim Smith <smitht@UNB.CA>
Subject: JBWeld and heads: 8 year report
In-Reply-To: <39CFEBA2.57F470D4@CONCENTRIC.NET>
Content-Type: text/plain; charset="us-ascii"
Hi All Vanagoons and Syncronuts,
A general FYI on JBWelding of heads
It works! Had to rebuild one side last week, due to burnt
valve. The DPO had heads done 3 years before I bought
it, making a total of 8 years. No drips to date except
in bitterest winter, -25C temps, and I'm laying the blame
there on hardened/aged rubber. When I got the head off
the seal still sat flat on top of the JBWeld, no serious
puffed up zones of aluminium oxide, no leak pathways. I've
taken off factory OEM's and found the seals literally cut
apart from oxide lumps pushing into it.
The seal was hard as a rock in some sections, still soft in
others, no explanation/guess why. What I did notice was
some oxide debris on the water jacket side, but only as
a film, no pitts eaten down. I cleaned that up with emory
paper only. This is the side that doesn't get any goop on.
The JBWeld still adhered strongly to the head, no sign of lifting
or delamination, nada. In fact tanking the head at the rebuilders
didn't get it off either, I had to grind it out with wire brush
and sandpaper. I cleaned it all until silvery before redoing
with JBWeld.
So for you facing leaking heads, $0.50 worth of JBWeld is a longterm
fix, bringing the wassleaker repair costs more in line with the concept
of a 'volks' wagen. Here's the short and sweet..... clean heads
with wire cup brush in drill, better would be sandblasting. Get the
loose oxide off and clean out the pits thoroughly. Sandpaper with a
flat block to level. Wipe clean and spread JBWeld over the entire
sealing surface (1/2" wide rim) using a single sided razor blade.
Spend the time with the blade to lay it down flat, squeegee kid
style, to fill the pits and leave a smooth surface. Let dry 24hrs and
fine sand with emory to remove any waviness. You just want it flat,
don't try to sand away all except the pits. Goop with favorite brand
and reinstall. This isn't like a conventional engine/head gasket. There
is (comparitively) tons of 'give' in that gasket, so don't be fooled
into thinking you need machine milled surfaces, rubber and goop fills
the gaps nicely, after JB fills the real pits.
HTH, Tim
PS: the 8 yrs is my low usage engine, maybe 50K miles on JB, my crew
engine (sold) had about 70K on it's JBfix. And remember, I went back in
because of a bad valve, not a wasser leak. :)
PPS: 8 years on Prestone green antifreeze too, changed every two years.
Studs are all perfect, not any sign of corrosion on them. Save your
money, live dangerously, boycott VW-Autobahn brand.
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