Date: Fri, 17 Jun 2011 23:08:07 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: locating my water/oil leak
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Hi Kevin...
well...
ah .....you gotta do waterboxer head gaskets right.
That's super creative to make your own outer rubber watergaskets.
That is of of course , only part of the sealing.
almost all other engines in the world have one flat cyldiner head gasket
sealing surface..
and it seals combustion, and cooling system .
And it's held down with huge force by head bolts that are really torqued
down.
the waterboxer though ..is purely a converted air-cooled design.
The combustions sealing ..
is done like they have always done it on air-cooled VW's ...
the head sits on top of the barrles, and reaches down around them about
3/8ths of an inch, and metal rings seal in the combustion.
the nuts on studs that hold the head down or torqued to only 37 ft lbs.
It works pretty much.
in an air-cooled if the combustion leaks past the metal sealing rings...you
get a popping sound under acceleratio or load, and loose some power. No big
deal.
In a wbxr, if that happens...you get exhaust into the coolant area,
displacing the coolant, and pretty 'good' overheating , or really bad
overheating.
but that's only about the combustion sealing, and it mostly works.
The other area that's sealed ..
is the outer water gaskets that hold the water in.
How well they are compressed depends on where the heads bottom out on the
tops of the barrels.
You can have that outer rubber water gasket gap too small..
which pinches the rubber gaskets there, making them leak sooner than the
shold..
or they can not be compressed enough .....and they'll leak.
Or the head can sit titled on the barrels and it's pinching the rubber
gasket at one end, and not compressing it enough at the other end.
it's so incredibly micky mouse, it's a wonder they hang together as well as
they do.
I have seen people leave out the small green o-rings at the top of the
barrels.
those are there to keep coolant away from the metal rings.
The green o-rings get hard and brittle in only a couple of years.
Did you attend to those ?
Did you measure your outer water gasket gap, with the head and metal rings
on , but not the rubber outer gasket ?
they usually do not get oil in the coolant.
the main failure modes are ..
external coolant leaks out the rubber outer gaskets.
Exhaust getting into the coolant , resulting in overheating.
and $ 3....consuming coolant in the combustion chambers and sending it out
the tail pipe.
there's not much oil/coolant interface.
in a 'normal engine' there is usually an oil passage through the head gasekt
to oil the valve gear on top of the head. No such thing in a waterboxer,
instead, oil goes up the pushrods to the rocker arms ...and drains back to
the sump through the push rod tubes...
so 'usually' you don't get oil in the coolant in a waterboxer engine.
I'd say take the heads off , use the real right parts, and very carefully
put it back together again.
you can do the heads with engine in the van.
waterboxers 'work ' ...but they have to be done fairly right.
That is very creative making your own outer water gaskets ..
I shoot for a 3.5 mm gap there ...which gives about 1 mm of rubber gaskset
compression.
It's very hard to get the 'step distance' ...the distance between the two
sealing surfaces machined by a machine shop. Most can't do it .
as they reference off the top of the head..
where to do one right in a waterboxer head you'd reference off the spot in
the combustion chambers where the metal rings are.
And ..the barrels can be pounded into the case some ..
throwing everything off a little.
what did you use for a sealant on the outer rubber gaskets ?
back to the drawing board it looks like !
scott
www.turbovans.com
----- Original Message -----
From: "kevin armstrong" <candleroz@YAHOO.CA>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, June 17, 2011 7:20 PM
Subject: locating my water/oil leak
Dear fanagons,
Just spent many many hours rebuilding a '84 Wasserboxer 1.9L and after
dragging it behind a truck to start it now have oil that looks like whipped
cappuccino. Drained the water system then the oil to prevent corrosion and
will be pulling off the injectors et al tomorrow to assess the 'head'
gaskets I fabricated out of two flat sheets of high-temp rubber vulcanized
together. However, is there any way I can know if the seals around my
cylinder sleeves are good or not without pulling them (i.e. dropping the
whole bloody show again)? There was no moisture around the candles and no
oil in the water system, only the opposite.
Like the van, but am losing faith.
