Date: Sat, 21 Jul 2007 19:00:53 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: Head machined or my way ...
In-Reply-To: <001301c7cbdb$4bdbc980$6401a8c0@TOSHIBALAP>
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Don't forget, fly cutting the heads can also change the compression ratio.
If only removing a few thousandth's, wont make much difference even for
the outer gasket.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Scott Daniel - Shazam
Sent: Saturday, July 21, 2007 5:08 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Head machined or my way ...
There is more to consider.
If you lower the sealing ring face in the combustion chamber , you also
need
to remove a like amount from the other cylinder, and a like amount from
the
main bottom face.
The relationship between those two places....where the rings go, and the
bottom main face... determines how much the head squeezes the 'water
retention rubber gasket' (a joke design if there ever was one. )
If you just 'flycut' the heads, and don't also surface the bottom a like
amount ........the rubber gasket will get pinched too much, and split and
leak after a while ( I learned this the hard way once....on a new head no
less ! ) .
What you should do is install the head over the barrels temporarily and
measure the water gasket space. One vw tech told me to do that and 'if
it's
less than 4 mm try another head' ....!!!..which is a joke since it was a
big
breakthrough when they invented standard size parts in the 20's ..
( ...at one time each part was custom fitted for each engine etc.....at
the
1922 world fair or something, it was a huge deal that they took 3 Buicks
apart, and swapped around all the parts and put them all back together in
different places and all the cars ran .....)
So when I heard that 'try another head' I really got a good laugh over
that.
I tried that on a head or two ...I found the rubber water gasket faces
not
parallel ...found it varying from 4 to 7 mm across the face.......what a
joke.
How the barrels sit ( they could be tilted slightly ) ...and how far down
the heads fit over the barrels affects that water gasket.
So, if you really did remove much material......you should consider doing
it
to the other cylinder, and a like amount from the bottom of the head, you
should to this 'dry fit' measuring.
Then 'next time' just put in a Subaru engine. They have head gasket
issues
sometimes, but nothing like the waterpuker joke system. At least they
have
'real' , and flat, head gaskets.
No rings and o-rings n' and air-cooled engine originated stuff like
waterpuker, er I mean waterboxer engines have. It's barely a viable
system.
Heck, even in the mid or late 90's you could nag VW of America enough over
this silly design to get them to pay for the repairs, even though the van
was out of warranty.
Scott
www.turbovans.com
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Zoltan
Sent: Saturday, July 21, 2007 1:04 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Head machined or my way ...
Although I have the tools and I can use a friend's machine, I elected to
superglue a 500 grit wet-dry sand paper, cut it close around the outside
and
patiently went back and forth for an hour with it, until it was even and
there was not sign of any scratch even looking it with a magnifying glass.
Then I used the Permatex "Copper Spray-a-Gasket" to install the
compression
gasket.
This way, I sleep well.
Zoltan