Date:         Tue, 30 Mar 2004 19:39:22 -0400
Reply-To:     Herr Wibo Fichten <wibo.fichten@ROGERS.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Herr Wibo Fichten <wibo.fichten@ROGERS.COM>
Subject:      Re: Valve guide removal / replacement
Content-Type: text/plain; charset="iso-8859-1"

Vanavitches,

Thanks all for the informative answers. I did quite a search in the archives
and I'm convinced the archives are much enriched for your postings!

The reason I was asking is because I am close to the 1.2mm wiggle specified
in Bently - with a used valve (no new one to test with )  But I think a good
clean-up and light lapping should put me back in business.

I'm reproducing a response from: "Doug in CA" <vanagon@astound.net who
P-mailed me a good detailed response that I think deserve the bandwidth /
archive space

Thanks again to all

Fichten

>
To: "Herr Wibo Fichten" <wibo.fichten@ROGERS.COM>
Sent: Tuesday, March 30, 2004 03:43
Subject: Re: Valve guide removal / replacement

The valve guides do wear out especially the exhaust side.
The intakes run cooler and do not wear as quickly.
You can check them for play with a new valve when the springs are out.
if you can move the valve side to side much they are worn.

We used an air chisel with a pilot end that goes inside the valve guide and
has a flat just undersize of the outside diameter. You drive them out from
the combustion chamber side to the rocker side. The guides have a shoulder
that bottoms against the rocker side of the head.

They come in various oversizes because when you press them in and out you
open up the bore in the head and you need a tight fit.  The inside diameter
is standard for the valve stems at I believe is 8mm or perhaps larger like 9
or 10mm. The air cooled beetle engines were 8mm stems.

Once you press in new guides you have to re-touch up the valve seats to
match or the new valves may not seat correctly.

Silicon Bronze is I believe still the standard,

Doug


----- Original Message -----
From: "Herr Wibo Fichten" <wibo.fichten@ROGERS.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Monday, March 29, 2004 8:02 PM
Subject: Valve guide removal / replacement


> Hello Vanagonites the world over,
>
> Has anyone ever removed the valve guides.  Bentley mentions nothing of
this
> procedure and the archives appear to be silent on the subject too.  Does
it
> require specialized tools or presses?
>
> Mine seem pretty well stuck in the heads and I would hesitate a long time
> before banging away on them for fear of bending, breaking or deforming
them.
> In fact except for a single picture in Bentley, that suggests it, I don't
> even know if they come out from the piston side or the valve spring side.
>
> The list vendors carry them and in several sizes.  They refer to oversized
> guides: are we talking of inside diameter or outside diameter?  Mine are
so
> tight (press fit?) I can't imagine it would be outside, but what use for
> larger inside diameters?   What is the purpose of these?
>
> Fichten