Date: Fri, 4 Sep 1998 12:46:24 EDT
Reply-To: GMBulley@AOL.COM
Sender: Vanagon Mailing List <Vanagon@vanagon.com>
From: GMBulley@AOL.COM
Subject: aircooled head torque, oil leak
Content-type: text/plain; charset=US-ASCII
Subj: Head bolts on Air cooleds oil leaks
Date: 9/4/98 12:30:16 PM Eastern Daylight Time
From: GMBulley
To: type2@bigkitty.azaccess.com, VCR50A@prodigy.com
To: vanagon@vanagon.com
At 4:33 AM -0700 9/3/98, MICHAEL G BENTHIN wrote:
>No one answered my query on oil leak from engine/cylinder connection in my
>78 Westy. So I went ahead and retorqued the lower head nuts while doing
>the seal work. Stopped it on one side, other side still leaqks a bit.
>Anyone know if this is worse than leaving it alone or know if the upper
>nuts can be reached? Would holes have to be cut in the tin?
<<<Snip>>>
...When the engine was put together it should have had sealant applied to the
base of the cylinders to prevent leaks. If this was not done, the only
real solution is taking the motor back apart, cleaning the base of the
cylinders and putting the sealant in. This is a lot of work (Probably 8
hours for someone that knows what they're doing) so if the leak is bearable
I'd just live with it until rebuild time.
David--
You've brought me temporarily out of "sniveling lurker" mode. I am G. Matthew
Bulley, tollerated mostly on the vanagon list, and former VW motorbuilder. I'm
not trying to flame the above writing, but there are a couple of errors in
fact, and you are considering some no-no's.
DO NOT cut your tin. never. That would be equal to drill holes in a radiator.
even if you plan to weld over it, the tin is made a certain thickness, color,
and dimension for very (German) calculated reason. Don't paint it, undercoat
it, cut it, whatever.
There is never any "sealant" applyed to the base of the cylinders. Never. the
base of the cylinder is a heat transfer surface--it transfers some of the heat
from the jug to the block, where it is displaced by splashing oil, taken to
the oil cooler, etc. The only thing that should be there is a very thin metal
gasket, which deforms slightly on torque, and seals and case to cylinder
imperfections. Your builder may have neglected to put these in. The only
remedy is to disasssemble, and insert them.
DO NOT worry about your upper head bolts. They never get re-torqued, NEVER.
They are about 1/3 shorter, and are on the "cool" side (the top) of the motor,
thus they don't stretch like the lowers. You torque them on assembly, and
that's it. The lower head bolts on the other hand, are on the "hot" side, are
quite a bit longer, and thus stretch. They are to be retorqued every other
valve adjustment (solid lifter VW's), or at least every 20k. NEVER torque
above the spec for your engine as you can hear a sound that will live in your
mind forever, the sound of a case stud popping out of the case. POING! If your
torque is correct and EVEN around the engine, and you still have this leak,
disassembly is the only option.
HOWEVER: I have (in a hundred or so motors) never seen a leak at the base of
the cylinder that was even worth worrying about. It sounds more like you have
a push-rod tube leak, which is much more common, spills a lot more oil, and
much easier to fix.
See you at BUGGOUT in Manassas. Stop by, have a free Diet Coke, and see our
1976 "silent" bus (for sale) Its's marigold Yellow, and has a blue side tent.
Good Luck.
G. Matthew Bulley
cary, nc
1982 White Westy
1985 Jetta Turbo Diesel
1976 "silent" bus (soon to be former owner)
.
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