Date: Mon, 17 Jan 2005 12:15:08 -0800
Reply-To: Robert Fisher <refisher@MCHSI.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Robert Fisher <refisher@MCHSI.COM>
Subject: Re: Head treatment for pitting--flattening technique
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I wound up doing the JB thing to my pitted heads after the machine shop had
taken them apart and thoroughly cleaned them; I sanded them down as best I
could with a block, mainly looking for bubbles (holes), etc. Everything
looked pretty good, but I knew I didn't have it perfectly flush, so when I
took the heads back to the shop to have them finished, they shaved the
mating surfaces slightly to get them flat. Now they understood about the
cylinder clearances and all that, so they just took off some very slight
fraction of an inch (don't remember exactly, might have been 1/100ths). They
figured that the gaskets and such probably had more give than what they took
off. Didn't seem to have any effect at all on reassembly or running; that
was probably 12,000 miles ago or more and all is well so far, assuming I
didn't just jinx myself.
Probably something you wouldn't be able to get away with more than once but
it seemed to be effective.
Cya,
Robert
----- Original Message -----
From: "Jim Felder" <felder@KNOLOGY.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Monday, January 17, 2005 7:50 AM
Subject: Head treatment for pitting--flattening technique
> I'm slogging through head replacement and have tried a technique that,
> while I can't say it's worked out well because I haven't run the car,
> seems worthy of mention for others contemplating the same procedure.
>
> I had the heads cleaned, then dremeled out the corrosion to leave
> bright, shiny pits and filled them with JB weld. Cured overnight. Then
> I spray-glued 100 grit sandpaper to 3/4 inch smooth plywood, mounted
> the sanding surface on a table, and sanded the head in a circular
> motion until all was perfectly--and I do mean perfectly--flat.
>
> I have pictures of procedure and results if anyone is interested.
> Everyone may do this, I don't know. But it saved me a couple of trips
> to the machine shop and went really quickly. I tried it wet and dry,
> both have advantages/disadvantages. I'd just do dry next time.
>
> Jim
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