Date:         Thu, 7 Mar 1996 18:09:07 -0700
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         rickgo@halcyon.com (Rick Gordon)
Subject:      

>        I took the engine out of my '72 to find the oil leaks, and wanting
>to find TDC (once and for all).  I took one head off and found no seal,
>gasket, or even spacer between the head and cylinder.  There was evidence of
>"blow-by" on both heads, and it appeared that the piston and head were
>keeping close company at the bottom - both were shiny - unlike the rest of
>the head and piston.
>         Do I need to stop here, not pass go, find the proper parts, or is
>this how a VW T4 engine does?
>        Bob Hoover was kind enough to answer an earlier posting in which I
>mentioned the blowby, and he said it shouldn't be in any engine.
>        I guess my main question is: is there something supposed to be
>between the cylinder and the head?
>
>        I wait with that old stinky 'baited breath' for the collective
>wisdom to educate me.
>

I've been told that it depends upon the heads. Some heads were made of a
material that was supposed to be soft enough to fit tightly without a
sealing ring. The Bentley doesn't show one for air-cooled engines either -
I haven't checked the fiche though (where did I put that thing?).
The fact that you're getting blow-by shows how well they work.
When I had this problem I had the heads fly-cut and then had sealing rings
(aka head gaskets!) installed. The fly-cutting makes up for the change in
compression ratio that would have otherwise been introduced by the gaskets.
And since you've got to pull the heads anyway, might as well take a close
look and see if there is anything else you can do while they're off! valve
leakage, pushrod tubes, checking for cracks, all come to mind.

-rick

Rick Gordon
Bainbridge Island, WA, USA
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