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Wheelman33
05-31-2013, 04:01 PM
We had the thrust bearing basically melt on our motor which caused a much bigger problem. Engine builder says something was pushing on the crank. Any ideas as to what could have caused this? Anything inside a standard Bert that could cause this? Driveshaft was not bottoming out. I'm clueless but dont want to put the motor back together just to have this happen again

82Motorsports
05-31-2013, 07:37 PM
The only thing that could apply pressure once motor & tranny is bolted together is the coupler bolted to the crank. And then for it to do so, the splines on your tranny input shaft aren't deep enough. i.e a clearance issue Driveshaft would have nothing to do with applying pressure to the crank as the tranny doesn't move forward or backward at that point. Did that make sense?

zeroracing
05-31-2013, 08:22 PM
It would have to be directly in the bell housing, trans, motor connection. For some reason did the splines have a major burr on them and or run out, had the bellhousing been surfaced...
Or was something wrong with the motor and it seems to hbe started around the crank area, taper in bearing surfaces, a burr of some type... All impossible things to know for the most part now but would not be suprised if the problem was on the motor side.

Egoracing
06-01-2013, 07:20 AM
Are you running a motor plate or mounts between the engine and trans?
If you are were you using a longer pilot bearing? If not the pilot was not supported the way it is supposed to and ate the bushing, this could have allowed the pilot bushing to go bad and that could have put some forward pressure on the crank.
If you are not running it make sure that the shaft is not to long on the trans for not running a midplate. Someone used to sell an longer input shaft for a Bert that allowed the bushing to be normal and get full depth in the coupling. Was a trick of the week but there may still be a few out there in used transmissions.

Wheelman33
06-01-2013, 10:35 AM
Makes perfect sense 82 motorsports. The trans went in easy but after the blowup it took a little pull to get it apart. We run a 1/4 inch motor plate....is it possible the input shaft slid through the coupler and was slightly pushing on the crank? We have run this exact setup for years with 0 problems except this was a new crank.

let-r-eat
06-02-2013, 12:33 AM
What brand crank?

dirty white boy
06-02-2013, 01:58 AM
has crank ever been turned?? if so machinist might have forgot to turn thrust flange causing your bearing to fail,..seen it on a stock motor local chevy dealer rebuilt...buddy of mine still has that crank on a shelf...

fox1162002
06-02-2013, 03:45 AM
Had a friend whose yoke was to long an it wore thrush bearing out in bert and when motor was freshened up thrush was wore out to the copper in the motor. the bert tailshaft wasnt splined all the way and yoke bottomed out. also bellhousing was cracked and bound up input.

racin6mod
06-02-2013, 05:44 PM
We had the thrust bearing basically melt on our motor which caused a much bigger problem. Engine builder says something was pushing on the crank. Any ideas as to what could have caused this? Anything inside a standard Bert that could cause this? Driveshaft was not bottoming out. I'm clueless but dont want to put the motor back together just to have this happen again

was the dust cover over the input shaft crack or broken also was this a drysump engine with a rear mounted pump. as a bert trany repairman I'm having a very hard time with his idea the trany took out the motor. I have seen it with a clutch set up were the throw out was over traveling and pushing the crank forward. that is not possible with a bert or brinn. if the coupler was spaded out enough to bottom out the splines on the input you should have noticed that when bolting the thing up as the bolts would have been tight way to soon and the bell housing would have most likely cracked.