Date: Mon, 6 Apr 2009 17:59:53 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Engine Rebuild Questions
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well, it sure is better if the guy has waterboxer engine experience.
They are not really quite like 'normal engines' ..........certainly not at
the head gasket area.
But hopefully he'll not get in trouble there.
1,500 for a total cost ?
that can't cover a 'real rebuild' .........that can cover a top engine job,
yes. Like new heads.
or it could cover the labor on a full split-the-cases real rebuild job .
not not for 'everything' for a real true real reubild.
at 250,000 miles something needs to be done about the crankshaft and
bearings.
at least carefully checked, if not machined and bearings replaced.
It's important to chceck the gap between the heads and the block.......
where the 'outer water gasket' goes.
If that gap is too small, the rubber gasket will pinch and leak after a
while.
if it's too large, the gasket won't be compressed enough , and it can leak
later .
if the head sits on the barrels tilted..............then the gap can be too
tight at one end, too large at the other.
none of this would apply if it was a 'normal' flat bottomed head ( where it
bolts on the block ) and a a flat topped block.........
like 'normal engines' have ......but it's nothing like that. It's a
converted air-cooled design .....
with a 'two step' head surface, and the distance between those two spots has
to be pretty close to right, becuse that distance determines the
compressing of that outer water gasket.
That's the main thing that's weird , and maybe 70 % of the time you can just
slap on a head and the outer water gasket compression will be about right,
but sometimes that area needs careful attention to get right. One vw
dealer technician told me once............'if it's not right, you try
another head' ........
which is bizzare since parts are suppossed to be standarized and all will
fit anywhere they are suppossed to. It's not quite that way with waterboxer
heads. Some fit better than others.
on most engines, the head bolts are creamed down quite a bit, like 100 ft
lbs say .......and the flat head gasket is very compressed, and the tighter
the head bolts, the more the head gasket is compressed.
In a waterboxer engine, the head bottoms out on the barrels, and the heads
are held to the tops of the barrels by the cylinder head nuts at 37 ft lb.s
of torque .............but that has no affect on the water gasket
compression , other than by distance. The head nuts don't compress that
out water gasket actually ............the ccompression of that gasket has to
be about right, not too much, and not too little. Very mickey mouse design
actually.
Good luck. Subaru engines have real headgaskets, of course, with flat
bottomed heads too. Upgrade to one of those !
2.1 engines are known for low oil pressure at the rod bearings after high
miles, due to stretching of the rod bolts. At 250K miles......
might be good to re-do that area for sure.
Scott
www.turbovans.com
----- Original Message -----
From: "Robert Stewart" <robertmstewart@MAC.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Monday, April 06, 2009 10:29 AM
Subject: Engine Rebuild Questions
> Good Monday to everyone,
>
> I have a local engine rebuilder working on my 2.1 Automatic engine
> which had roughly 250,000 miles on it.
>
> He informed my heads needed to be replaced. I could clearly see the
> space between the two valves having a indentation bridging them and
> the surface areas were very badly pitted.
>
> I planned on purchasing a set of rebuilt heads from Van-Cafe, anyone
> think this a good or bad idea?
> Anyone used them before? Have any feedback?
>
> Secondly is there anything regarding the rebuild that is a must to
> replace component wise since he has it all apart?
> i.e. sleeves, pistons, camshaft etc...
>
> I am awaiting a final parts list from him now but want to be sure I am
> not missing anything.
>
> Before he rebuilds it he is going to be cleaning all the parts in a
> special bath then glass bead blasting the non sensitive parts.
>
> Also how long should a standard rebuild take? i.e. 7-21 days? or is it
> something that can be done in a 40 hour work week?
> What kind of price should I expect?
> He told me it would be roughly $1500 dollars.
> He said he would be check to see if the camshaft needed to be reground
> and would check all valves etc. His shop only does rebuilds but of
> mostly race car engines and big truck engines so I trust he knows what
> he is talking about. He is not a VW guy at all he just knows engines.
> I did give him the Bentley just to be safe though.
>
> Any advice would be appreciated.
>
> Thanks,
>
> Robert
> NY
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