Doing another rebuild due to spun rod bearing. Is there such a thing as a bearing upgrade? This is for a '89 3.6. Thanks

 

Street car or race car???

There are MANY things that cause a spun rod bearing so my best advice would be to perform the detailed forensics to find out WHY it failed. Factory (dealer) bearings are just fine for the majority of applications, but you need to learn why it failed.

Remember, the entire oiling system must be removed and very thoroughly cleaned up to prevent a recurrence.

 

Steve I'm glad you saw this I was hoping to get in touch with you.

This is a street car that sees a handful of track days per season, more if I can get it running reliably.

Per my mechanic he says he did nothing wrong on the rebuild and it smoked 1 bearing to the copper and others had mild damage only after about 4 track days. I was having a problem with the front mount cooler not working properly and came off the track early during each DE session.

Mechanic blamed it on "the engine has heat issues" and "tighter tolerances after rebuild" and it "has a bit more power than stock"--mild ssport cam, Wong Chip--dynoed at 300hp at crank.

Could bearing failure happen so quickly on after a rebuild? What do I need to ask him directly I don't know enough about the engines to press the subject then pay him AGAIN for another rebuild if nothing has been diagnosed.

 

that's funny! are you going to buy that?

 

sml--that's my problem. Aside from taking it to someone else, which I still might do, I don't know how to diagnose it. Yes I was fully anticipating him accepting none of the responsibility of the bearing failure. He's been my mechanic for years and I'm having a hard time with the entire experience as this is the 4th season without my car.

 

Well,....I don't quite agree with your mechanic about the cause, but I'd need a LOT more detailed information. I've seen this happen many times when the oiling system wasn't properly cleaned.

Contact me directly to discuss. Best time for me is after 5PM PDT.

 

JMHO,.....

At this point, you REALLY need an independent agent/shop with plenty of experience to perform the forensics, since there is a conflict of interest if your current shop does it.

 

Mahle has bought Clevite 77 and Vandervell

http://www.mahle.com/MAHLE/en/News-a...a-March-9-2007
"The acquisition, which includes all worldwide units of Dana’s engine hard parts business including the Clevite® aftermarket organization, was successfully concluded as of March 9, 2007."

http://www.ebearing.com/news2008/061201.htm
"Mahle GmbH (Germany) has acquired Clevite Mexico SA de CV (Clemex; Mexico) and its subsidiaries.

Founded in 1959, Clevite de Mexico is Mexico's largest manufacturer of engine bearings, bushings and gaskets, under the Clemex brand. ISO9002 and QS9000 certified, customers include OEMs such as GM, Ford, Chrysler, Mercedes and Nissan, along with a strong aftermarket presence worldwide."

http://www.vandervell.co.uk/
"Vandervell is now part of the MAHLE group, so the best bearings in the world are now united with the best pistons in the world."

http://speedtalk.com/forum/viewtopic.php?f=1&t=29449

 

Sorry to hear that.

I'm sure Steve W or Indycam will have some good ideas on how to prepare evidence for your contract dispute.

 

I sure don't .
It could be the parts , the installation of the parts , the use of the parts .

 

All of the above, and a lot more.

 

Theo, find a new mechanic.

It would be easy to strap that engine to a pallet and send to any one of some great 911 engine builders on this forum.

 

Theo, To answer your question, yes, there are race quality bearings with intermediate sizes available so an engine builder can obtain specific clearances that he/she wants. They are available from Smart Racing Products. We DID have issues with stock bearings 5-6 years ago, but the failures were after a number of hours of track usage. I haven't used them since, so I don't know if there is still an issue. However, I'm confused by the "tighter clearances" comment from your engine builder. Typically, we run wider clearances than the factory to help with longevity, not tighter. If in fact tighter clearances are used, the oil temperature will increase.

We've had issues on cars where they've run a sprint race (30min) with elevated oil temps >250, and while not recommended or desired, there has been no sudden engine damage. Running at elevated oil temps will cause issues long term provided the engine tolerances are at least factory tolerances.

FWIW, we've run engines from stockish hp all the way to 700+ turbo HP in street and racing environments with a minimum longevity of 60hrs (high boosted turbo engines). Some of these have used a similar bottom end setup to what you have now. A standard 964 Cup engine runs 4 years of racing on a rebuild.

I hope this helps.

 

Jon & I had a long phone conversation this AM and established an exit plan out of this morass.

 

Thanks again Steve your advice is much appreciated.