Bill Ball

OK, this is incriminating. I see a large gap in picture 7. Is that it? Can you show a before and after moving the crank?

The face of the thrustbearing is copper after the top layer wears off.

blown 87

I know you were.

Bill Ball

That would be crank journal and/or crank throw material.

You have to pull this motor regardless (rebuild or replace). Get it out and get the girdle off the block, although it's largely academic as a $2K replacement motor (if good) is a lot cheaper than a rebuild even if the block is not cracked. Some part of the crank is in bad shape to produce all the ferrous metal shavings you found. I still think it is thrust bearing failure, severe enough to be fatal, based on the endplay and gap you mentioned.

Vilhuer

One side of thrust bearing might be almost gone and block can still be perfectly ok. That is if bearing hasn't turned around with crank.

Tony

The fact that he says it siezes up when hot is a death sentance...its too late, damage is done.
Bummer

Waynegs3

yes bill #7 is where I can have the crank "touch" the cap. So with that being said, is there any way to fix it or is it unfixable?

Tony

UN

Imo000

I've seen and S4 that had a TBF but the block didn't crack and it was fixed with a set of custom shims and early 32V thrust bearings. Saw it when it was all apart and then a few months later when it was running, so it is repairable, as long as it's not cracked.

Black Sea RD

Been watching to see what the outcome would be and the second set of pictures sure doesn't look pretty. The other information provided, especially the seizing while hot part, means this engine needs to be pulled, dismantled and gone through to make sure just what you have and what can be salvaged, as others already have said.

Also beware buying used Ebay engines from unknown sources. More than one Rennlister bought such a "great deal" only to find the engine wasn't that much better than their own.

Also start asking around for a mechanic that understands these 928 engines. Unless you do engine rebuilds for a living, the learning curve on this kind of job is very steep and expensive.

By the way, a good friend of mine lived in Alpine while we both worked in Salt Lake City. We trained for the St. George marathon around there. That was back in the early 1990s. Great little town and it probably has grown some by now.

Sincerely,

Glenn M

Wayne,
Doesn't look very good, good luck.

Bill Ball

Although the block might not be cracked and the thrust bearing saddle might be repairable with some machining and a shim, it's probably far cheaper to go with a good used motor - maybe not a $2K motor from eBay but a good used one from 928Intl (or wait for their Xmas 1/2 price sale when it would be cheaper than the eBay motor). If you are going to pay someone to repair this motor, assuming it is repairable, it would cost far more than swapping in a good used motor. As I mentioned before, pull the motor and take off the girdlle. Theoretically, you could take off the girdle without pulling the motor. A few have done that.

FredR

Wayne,

If you really have 1.5mm of end float then whichever way you look at it, the engine has to be pulled no matter what. Once the white metal has gone on the thrust bearing your engine basically becomes another disc brake. Seizure is caused by the white metal melting and then soldering the crank to the crankcase when it cools off.

You should not write off the engine until you have stripped and inspected it but sadly it sounds like a pretty safe bet that the engine is going to be toast. All we can do is keep our fingers crossed for you. With 1.5mm of end float my prediction is that the gearbox side of the thrust bearing will be very thin, the rear crankshaft thrust face will have been ground out and same for the crankcase web to some extent. Once all these things start going pear shaped it is also a pretty safe bet that the thrust bearing will have turned in the crankcase journal and that is probably what does the crankcase in completely as you wil probably see hairline cracks- if so game set and match unfortunately.

How sad that we keep seeing this from time to time.

I do not know the history but I presume you are relatively new to 928's and purchased this car from a careful owner? Have you any reason to believe the PO knew something was wrong and offloaded the car? Unfortunately this problem basically strikes without warning so it is quite conceivable that the PO did not know about it but it is strange how often the problem "comes to light" with a new owner. Coincidence?

You have my sympathies- this is not how 928 ownership is supposed to be. Let's just hope for the best.

Regards

Fred R

928mac

With that much Crank movement I agree that it looks bad.

I caught mine just in time as I don't believe it touched.

There was brass showing on my TB so I say I caught it just it time.

You need to pull the engine, I didn't but yours needs a closer inspection and measurements.

Here is what mine looked like







It is best to pull the engine and if you dont want to replace all the wire connector ends, remove the harness from the computers and feed it through the firewall. IMHO

blown 87

I have seen them look that bad and still be in factory specs, but just in them.

Yours was bad with out a doubt.
We have one in the shop now that is on the large side of the factory specs, it is getting a superclamp and bearings, plus other things.

What was the end play on yours? I think you told me, but I cant remember.

The point I am trying to make is just because one in inside factory specs it may indeed be bad.

I am going to say your end play was .015-.020 "

928mac

I'm sorry Greg i don't have my old endplay spec. I never recorded it. I'm Bad