Date: Wed, 28 Dec 2005 13:57:47 -0800
Reply-To: Robert Fisher <refisher@MCHSI.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Robert Fisher <refisher@MCHSI.COM>
Subject: Re: How easy is it to remove the intake runnersw ith the engine
installed ? (long)
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I could see the value of your earlier approach as a stop-gap to the proper
repair on an upcoming weekend, or especially as a roadside fix to get
someone down the road to a mechanic or safe haven, but to replace the whole
gasket with the RTV and then essentially seal the head to the case with the
cold weld... that is what we're talking about, right? I didn't misunderstand
something?
I guess my first question, beyond whether the thing will actually work or
not, is how is this going to affect the torque on the head? The main
pressure-bearing points are on the cylinders, but it seems to me that
without that even resistance around the edges you stand a good chance of
tweaking or twisting the head under operating temps and pressures,
especially since the cylinders in this case almost create a pivot point,
instead of how a head mates flat against a similar surface in a 'normal'
engine. The way you described having to remove the old rubber makes me
wonder if the edges haven't actually been pulled in toward the case already,
and what the effect of that would be if they have. I wonder if you can even
come close to adjusting the rockers if the head has a twist or bend in
it...?
I won't get into the whole sad mess of my engine semi-rebuild here, but
briefly, it had been overheated however many times within some 12,000 miles
(IIRC) of a 'rebuild' and the PO let the beer mechanic at it and that was
that. In trying to get the passenger-side head off in the van he pulled the
cylinders over the rings, destroying some of them in the process. He then
gave up and it sat that way for a while.
I took the heads to a local import mechanic (a VW guy) and he gave me the
straight dope. They needed replacing, on way or another, but I didn't have
the cash. They were pitted all 'round the edges and cracked between the
cylinders. I took the heads to 'his' machine shop (the one he uses) and they
cleaned them and bead-blasted (?) them, did the valves etc. I then filled
the pits with J.B. and they milled a thousandth or a hundredth or something
off of the surface- not enough that the gaskets couldn't compensate for the
missing metal, but enough to make it flat. They also 'fixed' the crack. They
(the mechanic and the shop guys) all made it clear to me that this was a
compromised engine that I shouldn't take off across country with it, but
they figured I might get 50K out of it if I stayed on top of it.
I got the full gasket kit and the rings and re-did the top ends. Almost
three years later and the thing runs tight as a tick (I wish I could say as
much for the rest of the van). I don't even get the lifter clatter that
everybody complains about.
I did all that knowing that I was looking at a rebuild or conversion sooner
than later, but as it was going to be our daily driver (kids and all that),
I didn't want to take any more of a short cut than I had done already . It
gets to 120 here in the summer, so the condition of the cooling system is
even that much more of a concern, to my mind. It's never leaked a drop at
the heads... leaked more than a drop other places, but not at the heads.
I guess my point is that, having been through that and given your
circumstances as you've described them, I would still try to pull the head
without the cylinders (a la Benny), 'fix' the pits, put a real gasket in
there and hope for another 20k or whatever. I really have to wonder about
the torque factor the way your doing it; maybe somebody with some objective
insight can comment on that.
Good luck,
Robert
----- Original Message -----
From: "Roger Sisler" <rogersisler2000@YAHOO.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, December 28, 2005 7:35 AM
Subject: Re: How easy is it to remove the intake runnersw ith the engine
installed ?
> Thanks so much Robert ! I am glad to now know the holding stregnth of RTV
> sealer. Before, I must admit, I had my doubts. However the JB will back
> this RTV up and support it from blowing out someday.
>
> If this works, I hope other people can use it too. There are many reasons
> one may need it. For me,once again, my WBX has 187K and the head are
> certinly pitted and probably cant hold the pressures like they once did.
>
> What are my options?
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