Date: Sun, 27 Jul 2008 16:57:58 -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: External block damage and my plan to deal with it
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well......
things have to be clean of course in the weld area.
to late now .........but the right way to weld on a casting like an engine
case is with just the bare casing, not with parts like pistons and so forth
in it.
Be interesting to see what they say about it.
I had a very interesting cracked engine block episode- though cast iron. It
was a fully reubilt to the max 1.6TD ......and some goofball who shall not
be named tried to bolt it up to a trans with too long an input shaft.
Thinking things were 'just binding' said goofball finally just kept
tigtening things down ( such a dufus ! ) . This resulted in a 5 inch long
crack at the flywheel end of the block.
Got the block stripped to bare metal in a few hours. I had a friend at the
time who is one of the best welders I've ever come across.
We heated that block on a charcoal fire for hours, then arc welded the crank
with nickle rod I think.........and the final trick for the welding part was
to burry it fully in sand, and let it cool very slowly overnight. Then I
had the rear face of the block sufaced ( it was out by .003 ) , and ran that
engine non-turbo for years in a vanagon. And this crack episode was only one
of three 'should have killed it' things that happened to that engine.
hope they can fix it really well. As you know I'm sure, it's very classic on
2.1's especially that the alternator gets loose on the bracket. and left to
vibrate like crazy for a long time, it will do just what you have
discoverd - break off the studs. Perhaps it was misplaced drilling that
messed up the one bolt hole.......
But perhaps it's repairable. I'd sure rather have the bare casting to deal
with for welding though.
Personally, I wouldn't assoicate severe overheating with studs being
weakened or stud holes being weakened in the case.
The only failure mode I've seen of the studs is them breaking off at their
base - from corrosioin there, and from the nut on top being very corroded to
the stud. so far, in what I've seen, if they don't suffer from that,
they're OK.
also.......I gotta say - in my perception, the head studs on VW oppossed
alumninum block engines - not the same as a cast iron block where head bolt
torque is 60 to 100 lbs, or so many ft. lbs plus a few scary quarter turns
more - in other words........there isn't that much force on waterboxer
cylinder head studs in a waterboxer, relatively speaking. I've sure never
seen a stud pull like the old air-cooled did ones did all the time. Except
for them breaking off in the dissasembly process..........I've not found any
reason to worry about them. Your mileage may vary !
scott
----- Original Message -----
From: "Jim Felder" <jim.felder@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, July 27, 2008 4:31 PM
Subject: External block damage and my plan to deal with it
>I am in the middle--or maybe just past the middle--of a rebuild of my 2.1.
>I
> decided not to use my block as I suspect as hard as it was driven without
> coolant (not me) I could not trust the studs. I picked up a used engine
> without heads with a block that looked pretty good at first. It was only
> AFTER I got the pistons and sleeves installed and was thinking about
> transferring bits from my old block that I first noticed the damage: one
> of
> the holes for the stud holding the alternator bracket has about half its
> webbing cracked away. There is no way it would hold a stud. And it gets
> better--
> It seems that this is an earlier 2.1 block than my 90 and had a different
> style of alternator mount. My mount has two holes for studs in the front
> surface of the block, and that's it. The "new" block was obviously for a
> different bracket with holes drilled down through the 1/4 inch thick web
> of
> metal that extends out from the oil tower area. Of the two places for
> tapped
> holes in my original block, the new block has only the inner (nearer the
> crankshaft) hole drilled and tapped, meaning that the outer one can still
> be
> drilled and worked just fine. The inner hole has half of the surrounding
> metal torn away, but not all the way back to the water jacket.
>
>
> Anyway, I'm wanting to use my bracket and don't like the idea of depending
> on those two vertical holes through the thin part of the block casting. I
> plan to take the whole #$%^$%& engine to a welding shop (why couldn't I
> have
> seen this before I built it up?) and have the missing metal replaced with
> aluminum. The only thing that bothers me is that the welding is right
> there
> on the right water jacket. When I get it back, I will make a jig for my
> floor drill press to allow me to drill into the metal fill and tap the
> holes.
>
> I'm almost certain this shop can do this, I haven't asked them (closed for
> the weekend, obviously) but they are very good. Anything I should be aware
> of before I haul the engine down there?
>
> Thanks,
>
> Jim
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