Mopar thrust bearing failure

[BillK]

Originally Posted by devo340

Took it to our first race this season, lost #6 rod bearing.
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May be coincidence, started having problems after the trans was checked out.

I don't see how the trans would have caused a rod bearing issue. What did the thrust look like at that point ? Are you using the same bearings as before ? Same clearances ? Just curious.

[FED 387]

Bent crank-- trans crooked---convertor ballooning--- insufficient oil / lubrication---dowel pins not zeroed in ---- Fed387

[S/ST 3040]

I wiped out the thrust bearing in my 340. After a lot of thought, I determined the failure came from
stacking the weight of the engine and transmission on the driveshaft at the hit. I had eliminated the
engine mounts and was utilizing an engine plate and OEM transmission mount to locate the engine.
After the crank repair, I added a fore and aft limiter. I've had harder launches since then and no sign
of thrust failure.


The first thing to identifying the culprit is asking, "What changed?"

[devo340]

One other thing was changed, weight of the car.
Was at 3640, now @ 3750.


Crank is internally balanced with Mallory metal.
This is why I elected to have it repaired.
To avoid the cost of rebalancing another crank.


Rob & Main bearings have been changed every time.


I am going to change out the crankshaft this time & have the line bore checked & corrected if need be.
Since I'm new to this type of racing, anyone want to recommend a crank shop?

[David Lee]

where are you located?

[devo340]

Originally Posted by David Lee

where are you located?

Oklahoma.

[David Lee]

Originally Posted by devo340

Oklahoma.

see if mike cotton is still in the area, if anyone would know it would be him