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Re: LOOK OUT! SHE'S GONNA BLOW!!!



>  When I took off the #1 & 2 cylinders,
> everything looked pretty good, except the ring gaps weren't very well
> aligned, and #1 had been blowing past the rings.  On to #3 & 4, when I
> pulled the cylinder for #4, I found that the piston pin retainer ring
> was no longer with us, but we had a new friend in the form of a 1/8
> inch, piston pin-shaped groove in the cylinder wall.  One other thing I
> noticed, the edges of the piston pin hole on BOTH sides of the #4 piston
> were badly misshapen, one side I can understand, but both sides?  Just
> to clarify, I mean the edges of the snap ring grooves looked like they
> had been sandblasted round - no square edges like they should have had,
> and the edges of the holes were both "not round", for lack of a better
> term.  It made me think of some non-contact wear, like erosion.  Freaky,
> and pictures are on the way to 'splain that one further.  I pulled #3
> with no festivities (or major problems, I mean, that piston-pin trick is
> a tough act to follow).

This IS wierd!  It is possible that the retaining ring was just not 
installed properly, but I would also check for a bent connecting rod 
or a cracked crank.  Check the rod by holding the side of the small 
end flat against a flat surface and looking to see if the face of the 
big end is parallel to the same surface.  Check the crank by removing 
ALL the parts from it and then dangle it gently by one finger and tap 
it gently (in an unimportant place) with a small hammer.  If it is 
sound it will ring like a bell (Diinnggg....)  If it is cracked the 
energy losses in the crack will damp the vibrations quickly so the 
sound will die quickly (Dunk.)

The same trick works on any one piece part made of steel.

>      I started on splitting the case, everything went smoothly there
> except the bakelite spacer for the fuel pump broke inside the case.
> Once I got the case split, I found that the case had been pounded pretty
> badly (I think, opinions?) by the crank, as I could read all the bearing
> markings in the case.

The think to look for is a ridge around the center of the #2 bearing 
saddle where the bearing DIDN"T beat the case out (since that bearing 
has a grove all the way around its outside.)

  BTW, all of the bearings (cam and main) looked
> like sh*t, like when aluminum galls - you know that rough texture?

Surface texture like this cauld just be a sign that the oil wasn't 
changed often enough, I'm not sure.

> There was a good-sized collection of half-parts in the oil sump, looked
> like some washers and some generic metal chunkies.

Pretty normal.  The half washers are the remnants of the valve stem 
seals.

>  The lifters are
> totally flat, and the cam has rivets holding the gear on.  I wonder,
> does this mean it may have never been rebuilt, or is it possible that
> the cam was replaced by a factory part?

Sounds OE.  You could probably reuse all these if you put the lifters 
back where they came from.

>  There was no evidence of
> o-rings around the main studs, and there was some liquid (judging by the
> overspill) sealant used around the case studs, but there were paper
> gaskets under the cylinders - like factory.  How do I "read" this thing?

Stud O-rings started later than 66, but you can modify the case to 
take them; just countersink the easy side of the case so a ring will 
fit there.

>      I went on to the connecting rods, #1, 3, and 4 bearings show heavy
> signs of galling.  You'll notice I didn't mention #2 there.  #2 had
> spun, but probably some time ago in my guess/judgement.  Picture if you
> can a paper-thin flanged bearing, kind of like a cam bearing except
> bigger and thinner, make that really thinner.  I'm guessing that the
> noise this thing was making was a combo of the piston pin and the #2 rod
> bearing - remember, it WAS STILL RUNNING!  The crankshaft is pretty beat
> up, with scratches on the #2 rod and (I'm guessing on the number here)
> #4 main - the one nearest the flywheel.

Have someone measure the crank.  If the diameter is okay, it can be 
polished and reused.  The 66 crank should have only one oil hole per 
rod journal, 67- came with two.  The later crank is better, but you 
would have to change the flywheel, too.

Jim
-
*******************************
Jim Adney, jadney@vwtype3.org
Madison, Wisconsin, USA
*******************************


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