Bill Ball

Most of your thrust bearing is still there. Wayne's isn't.

Black Sea RD

Brad's picture of the old thrust bearing showing a lot of copper is just before the crank catches it and spins it around, ruining the block and usually the crank. Very close call!

Really hate this TBF stuff...

BPG_Austin

My thrustbearing was very similar to bwmac's. Crank runout was .019".

Waynegs3

Hey fellas, thanks for all your great input. I’ll pull the motor and take some additional pics. But, if it’s going to cost a lot of $ to have machined etc, then, Ill opt for a used motor... which then leads me to the risk of another bad motor.
So... in regards to a used motor, I have been in conversation with a guy from eBay, I’m sure some may have seen it.. it’s an 88, 59k miles. He from a wrecking yard in NH. He says the 88 auto s4 was rolled but repairable and he drove it around his place, but after 60 days or so, he dismantled it and started selling parts. He has documentation of the 59k miles. Is willing to do a compression test etc. He is asking $3k which seems steep, but we haven't got into the negotiation yet. Anyway, I’m sure I could get an oil sample and send to Blackstone for analysis.
What are some of the things I should have him test, or things I should be looking into, before I get my arms around another motor?

Also Fred R, in regards to your note. Yes, I’m new. I bought 4 sharks at an estate sale in NorCal. 93,90,88,87. Picked them all up for 25k. So I got a good deal, even if one had a bad motor. There was really no way the trustee could have know, as he was really clear that he didn’t know anything about them so I took a gamble. When Bill and Kirk took the end play measurement, the trans inspection plate was missing the rear most bolt, so it looks as if someone took a measurement before. The original owner, Duane had sadly passed away of cancer at 54. Very sad. With no family members to speak of, he obviously poured some of his love into these sharks.

So, I have continued his legacy.

Lizard928

You need to have a leakdown test done, as well as have him measure the crank end play. This will ensure that the motor is in usable condition.

And unless he offers a year long warranty on it, and has a spare to back it up, then I would say $2k is a better more reasonable price.

Erik N

You have Duane's cars? I worked on a couple of them w/ him over at Dan's place. The black one ('88?) was on the tilter for a while for a TB/WP. I think he got around to putting new Bilsteins in.

namasgt

I would recommend getting the VIN number of the car (for checking on car fax) to see what are the true miles....

I was buying a S4 engine once that they claimed it had 50,000 miles on it, checked car fax, it ended up having 170,000 miles on it. Remember that the odometer breaks easily on these cars and too many people/dealers rolled them back to make more money during a sale before carfax came along on the internet.

Colin is right, 2000 tops, unless he can back it up with warranty or a replacement one.
He should also put the oil filter back on before anything gets in there.

Speedtoys

There's alwys the risk free route:

http://www.mailordercentral.com/928i...100%20940%2044


And..well...how long can you wait?

Xmas sale.

Waynegs3

Hey Erik, Id love to talk to you about these cars. I am totally blind here on their history and if you have any additional info, it would be so much appreciated.

Also, yes, Xmas sale for sure. :-)

SnakeFeeder

I've always read references here re thrust bearing failure being due to the drive shaft creeping forward...but here is an interesting article that seems to put more emphasis on oil viscosity:

http://www.landsharkoz.com/tech/bb/bbipr.htm

Any thoughts on this?

SnakeFeeder

oh....and another one:

http://www.landsharkoz.com/tt/tttbf.htm

Imo000

Unless you see them take the oil sample from that engine, the oil analysis is useless as it could come from any engine in their inventory. As suggested above, have them check the end play and put it on a video clip, same for the leakdown test. I wouldn't trust a junkyard, many lie just to make a buck.

Waynegs3

OK, thinking about this a bit more... It never actually sized, it cranks over very slow when hot...like the starter motor is going out, or a poorly charged battery.

Mongo

That is a total symptom of TBF.

Waynegs3

Hey guys,
finally tore down the block and whallah..... block is cracked. center journal, very fine crack, but non-the-less, crack just the same. See pic.
So, car is a 90, auto.... what engine is the best to replace it with? 88? 89? 90? 91?