Date: Mon, 28 Jan 2008 21:27:57 -0800
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: uh-oh
In-Reply-To: <0D5AC2A3-3B71-4E53-A8E9-D28B217FACDF@cs.indiana.edu>
Content-Type: text/plain; charset="us-ascii"
Hi,
Personally I don't think retorquing is an option much as the head nuts have
sealant on them, and that seal will be broken loosening and retightening the
head nuts. ( and that sealant on the nuts is sort of an example how the
waterboxer is just a converted air-cooled design, but you don't want to hear
that anyway ! )
But that's not 'the problem'.
I just had the same thing happen on one side of a 2.1 about 4 months after
doing a full deluxe head and valve job.
Just started seeping on the left head, at the very same time friends were
leaving for Burning Man in it. So I need 'a miracle' .................they
could have made some arrangements, but with just one night to fix it I
wasn't going to be seeing any machine shops or anything.
I pulled the head. 'the problem' is how much, like how 'too much', or how
'not enough' the water gaskets get compressed between the head and block.
This is determined by the 'step distance' or relationship between where the
metal rings on top of the barrels sit ( like the outer circumference of the
combustion chambers ) and the flat surface of the head.
( I got that relationship from a machinist once, in inches or mm , and have
it somewhere, it's not in Bentley. )
So I pulled that head, put it back on without the outer water gasket and
measured the gap there. And I got3.5 mm.
Then I measure the thinness of the water gasket- same thing .............3.5
mm. So the gasket was not getting squeezed at all !
I use really great black Toyota sealant on both sides of the water gasket, ,
but obviously it didn't hold with no gasket compression there. And it was
'barely' a seep too. Like if out on the road, they could've just put in
some Bars Leak and been fine. But the one guy was really nervous, so I knew
I had to take it apart.
So I figure I need .5 mm compression on that rubber gasket.
I measure the rings on the top of the barrels, 1.00 mm thick.
So..............some rings only .5 mm thick would do it.
I look in my old dead left over weird gasket box, and low and behold, 4
rings .5 mm thick !
What a miracle. Like this is at midnight too. Must be from some air
cooled gasket set from years ago.
I put it all back together on that side with the .5 mm thick metal rings. .
Compression ratio has to be higher on that side. I just leave the green
o-rings alone as they're fine.
It went to Burning Man just fine, still running fine today. The other side
has never leaked.
And, no one is checking this dimension much I don't think. I first ran into
it about 15 years ago, I put a new AMC head on one side of a vanagon, it
went to Montana and back just fine. Then one day the guy shows up - he was
up in the Sierra mountains in California and it starts leaking, ( this
after about almost a year in use ) ..........that shop hits him for another
new head and gaskets, .............he sees me about it, and I say, well, let
me find out what the real story is.
I checked with *everybody* ..........oh, on that one the water gasket was
pinched and split, making it leak. ........finally I talk to a VW dealer
tech, and he tells me.............get this .............he tells me that you
try the bare head on the block, and if it's under .......whatever he said,
3mm maybe, if it's to small, you try another head !!!
Which is absurd due to the fact parts are supposed to be standardized and
built or machined to spec. I just had laugh. I still have that AMC head,
I've put it on other engines to check it - it's twisted, or not level
......its' junk. And it's new ! The waterboxer is a joke design in that
one area for sure.
So there you are - that 'squish distance' has to be 'about right.' And I
am certain that the water gaskets are 3.5 mm thick. I measured that 5 times.
So 3mm gap, head to block is right.
Either treat it with Bars Leak, which is the ONLY stop leak I recommend, and
I have never had it cause any problems ever. Or take the head off and
measure things. I even re-used the water gasket as it was just fine.
Or, I have another idea too, since you should just really go to a subaru
engine anyway, I'll take this engine off your hands as a
favor.................. just joking !
Scott
www.turbovans.com
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Allan Streib
Sent: Monday, January 28, 2008 7:31 PM
To: vanagon@GERRY.VANAGON.COM
Subject: uh-oh
Well changing the oil tonight I noticed a very small drop, but a drop
nonetheless, of coolant on the center bottom of the passenger side
head, at the rubber gasket.
PO said the van had recently had new heads, this claim supported by
the cleanliness of the heads, brand new pushrod tubes, etc. So --
what's my best first action to address this? Do the heads need to be
retorqued after they are run in for a while?
Or once they start leaking is it a lost cause and they need to be
pulled and re-sealed?
Allan
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