Date: Wed, 19 Mar 2003 08:41:40 -0800
Reply-To: gary hradek <hradek@YAHOO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: gary hradek <hradek@YAHOO.COM>
Subject: Speaking of head gaskets
Content-Type: text/plain; charset=us-ascii
Ed,
It is safe to use common sense here. The fit that
seems to determine the torque amount is that which
fits the head to the cylinder with the mating metal
ring. The rubber has no impact on this limit. This
is very different from the old gaskets that fit on
engines I have done in the past. It is my thinking
that to retorque the engine does more harm than good.
If you did it right than your job is done.
I believe mark has a different problem. It is
hard to believe that the pinched fit of the rubber to
the lower portion of the engine could fail so many
times at that same point unless thee head is not being
torued down fully or perhaps properly. I am sure
there must be several ways this can happen. For
Marks sake I hope it is discovered soon. I do not
think looking at pits points to the problem for mark.
Mark, if your reading this I hope you share your
solution and don't get discourgaed. gary
Date: Wed, 19 Mar 2003 10:19:09 -0500
From: Ed Carroll <ecarroll@MAINE.RR.COM>
Subject: Speaking of head gaskets
I was interested to read the thread of Mark
Vermillion's head gasket =
problems recently, since it was a pretty good thread
with lots of tips
=
about surface prep and gasket/head reassembly. Too bad
I was away from
=
e-mail and on my back in the garage for three days
reassembling the =
gaskets and heads, or I might have learned something
valuable.
I was bummed to see Boston Bob's brief treatise on
deburring the water
=
jacket and putting sealant on the inside of the gasket
as well. Somehow
=
I had missed this in my research, and I paused for
quite a while when I
=
had everything clean and ready to reassemble, searched
my notes from
the =
list, read the Bentley and Haynes and the magazine
article from the =
Vanagon.com site, and decided that while it seemed
like common sense I
=
would not put sealant on the inside. None of the
sources said to, so I
=
went by the books. (Now I see from Ben Huot's site
that he says VW says
=
to use sealant on the inside.)
I inspected the water jacket thoroughly, cleaned the
mating surface
with =
brake cleaner and used Scotch-Brite and then fine
emory cloth. There
was =
one divot on a jacket surface that looked like a
little tool whack from
=
some earlier repair work. More of a dimple really, and
I generally did
=
not want to work the jackets over too hard as I was
concerned that =
messing with them might make them worse than I found
them. There was no
=
other pitting.
The heads themselves had minor pitting, and I smoothed
a thin coat of
JB =
Weld over them, sanded them smooth and re-cleaned any
residue. Since
the =
engine is in the van and the van is on stands, it was
a PITA working at
=
3/4's arm's length over my head on my back, yet since
I saw no way to =
put sealant on the head side of the gasket before
putting it in place =
without making a mess of the sealant bead, I had to
put the gaskets in
=
place and do my best to put the black silicone that
came with my gasket
=
kit on neatly. A little work with a popscicle stick
and I was confident
=
that it was a continuous bead without any great danger
of splooging =
inward.
The head that needed the most prep work had an
exisiting gasket with a
=
semi-obvious inch and a half crack of dried out
fatigue that went all =
the way through, but would only open to daylight if
you pried the edges
=
of the inner seal apart a little. The most amazing
thing was to find =
that one of the aluminum cylinder seals inside that
head had become =
weirdly distorted at some point. It was still flat and
had apparently =
worked as a seal to the cylinder, but it was out of
round by about 3/8
=
inch -- like an "O" with a flat spot. Its shape was
clearly marked by =
the carbon deposit on the combustion chamber portion
of the head,
though =
there was no sign that the cylinder had been misfiring
or even leaking
=
there, and the van didn't run like it had caused any
real problem. The
=
head cleaned up fine, the cylinder was fine, and the
new rings seated =
just fine. There was no real corrosion or pitting
inside the rim in the
=
heads.
So here's a question: The heads are on, and after 100
or so turns
around =
the tightening sequence I still need to check the
final torque once
more =
before continuing the reassembly. Should I take them
off to re-check
the =
water jackets and put sealant on the inside? I think
not, of course, =
unless there is someone out there vehement about the
importance of goop
=
as lube ...
Ed Carroll
87 Weekender
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