Date: Mon, 17 Sep 2007 15:01:37 -0700
Reply-To: Scott Daniel - Shazam <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Shazam <scottdaniel@TURBOVANS.COM>
Subject: Re: Cooling questions still
In-Reply-To: <A2F96EB7AEDA4D49B2528EB7C04976B7226DDF@svrsbs3fds.FDS.local>
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The only time I will ever touch a waterboxer head nut is if one nut is
leaking, and that's the only leak, and maybe you can undo and reseal and
retorque it.
Otherwise, if you saw a typical waterboxer engine with the heads
off.....what seals the exhaust into the combustion chamber is one metal ring
sitting between the head and the barrel. It's derived directly and exactly
from the air cooled 1600 design. And it was fine for years that exhaust
gases leaked past the metal rings on air-cooled 1200's, 1300's, 1600's
etc....made a popping sound under load. Heard a million old Bugs running
around that way.
Now, in their cheapness, and 'theoretically can work' german
idealism.....they took the exact SAME design, and CONVERTED it to water
cooling.
The next 'sealing feature' after that metal ring at the top of the
barrel......which after a long time just doesn't seal that
perfectly....there's a green o-ring. This green o-ring keeps coolant from
contacting the metal ring. These rubber o-rings get brittle or gummed up
after a long time, and can't work. Bottom line - it's a mickey mouse system
to begin with, heads should just be pulled after 80K miles anyway and
resealed......so chances of getting it to seal again by retorquing are
basically nil - like 'a most remote *maybe* if you have to get back from
Mexico, and that's just to get home one time ' . I'm surprised no one
hasn't made a much better retrofit sealing arrangement there. As it is,
stock, it can only work for a while. You might notice that not one other
manufacturer on the whole planet has such a mickey mouse head gasket sealing
system.
And, not to go on, but we haven't even started to talk about the 'outer
water retention' gasket, and they have their own issues as well- primarily
how well it is compressed, which is determined by how far down over the
barrels the head goes.....I've seen engines where the space for the water
gasket is too large, where it's too small, and where the surfaces aren't
even parallel !
Anyway - retorquing ...not much hope I feel. Also.....you want to be sure
the nuts unscrew from the studs, and not have a stud break off down in the
case, at the bottom of the stud. Doesn't happen too often, but it's been
known to happen, and then you really are in trouble.
Oh right - wanted to share this. One guy told me how they ended up
with the waterboxer engine the way it is -they told the engineers at the
factory that they had 30 days to come up with a watercooled version of their
air-cooled engine. I believe it !!
But we love 'em, and they are GREAT vehicles. Think of it as an aircraft or
car racing engine - after so many hours of operation, you pull the heads to
reseal them and do a basic valve job, like standard procedure.
scott
www.turbovans.com
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Stephen DeMocko
Sent: Monday, September 17, 2007 10:14 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Cooling questions still
Ed,
I think Ken is right about the combustion gasses leaking into the
cooling. That is what mine was doing. How does the list feel about
retorqing the heads if the outer coolant seal is not leaking? I know
there is a chance of displacing the sealant under the head fasteners,
but it would be easier than pulling the heads all the way off to replace
the copper ring.
Stephen DeMocko
('85 Westy Luci)
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
Of Kenneth Lewis
Sent: Monday, September 17, 2007 8:54 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Cooling questions still
Ed,
The internal head gasket may be leaking combustion gasses into the
cooling
system. Do you notice a steady stream of bubbles into the reservoir(the
tank
with the blue pressure cap)? The water pump could be shot. The
thermostat
stuck, radiator clogged(does it get hot?). Does the radiator fan work on
all
speeds?
Ken Lewis
http://neksiwel.20m.com/
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