----- Original Message -----
From: Paul Schiemer <schiemer@MAGICNET.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, December 09, 1999 2:32 PM
Subject: Re: Red Flag! was need engine for '87 Westy

I couldn't agree more. I currently have a '90 Caravan sitting in my back
yard with 2 new heads.  Those new heads leak because that old cast iron
block "warped" a few thousands and now the head gaasket won't seal at at the
oil galley between cylinders 1 and 3 due to the fact that the block has
.003" warp to it in that area.
> Although 'warp' may not be the correct word, what is being referred to is
> the way certain parts 'face' each other after long term wear and tear.
> Since the engine case is made up of at least three main pieces, and
> connected to it are cylinders of a different material (steel), upon which
> heads are bolted (again, of a different material) there are certain
ravages
> that occur over time, just because of the way the different materials cool
> after use, and different pieces cool at different rates.
>
> Some after market heads are not 100% aluminum (nothing really is I guess),
> and of questionable quality in manufacture; you might find that -after
> extended use at maximum temp- they will lose their 'face'. This can lead
to
> all kinds of problems. Of course, they may be twisted to begin with too.
>
> While we may be talking about only a few thousands of an inch, it takes a
> machine shop with specialized tools to 'resurface' a head. This refers to
> the point where the head comes into contact with the mating surface of the
> cylinder.
> Between the cylinder and the case are a series of copper gaskets that butt
> right up against the case, the cylinder pressing down upon them. The cases
> themselves can, under the correct set of conditions, change their 'face'
> along the line bore, or longitudinal axis. This can be especially telling
> when you try to seat your crank or affix a main seal.
>
> An average schmo, or even jaded mechanic, cannot tell from looking at the
> outside of an engine these (often) microscopic differences are there. What
> the wizened old mechanic can do is look at the symptom and hypothesize the
> condition exists.
> To say, carte blanche, an engine is "warped" and you need a complete
> replacement may be more indicative of a mechanics' business acumen than of
> an accurate diagnosis. At the same time, the same mechanic may have been
> down that road of doing the proper repair, and having it cost as much as
an
> R & R.
>
> >Sounds like a mechanic's mumbo jumbo two step dance trying to get out of
> >re-doing a failed head replacement job.  You may need to bring a large
> >friend with you who understands Vanagons when you go back to talk to
> >this guy.
>
> It's all too easy to point a finger at a mechanic who has ten to thirty
jobs
> in queue, tends to use 'abbreviated' jingo to make his point, and trying
to
> do the right thing for the customer (thinking of wallets usually). They
> aren't ALL trying to steal your money you know.
>