HD SYE shaft replacement-lock-up

Problem is : The output shafts lock up when case halfs are bolted together,
The kit is a CollinsBros HD SYE kit.A 231 rebuild kit(bearings&seals) new chain and a new pump from the dealer.
As long as the pump is left off the shaft when the case is bolted together the shafts will turn.Trying the old pump yeilds the same results-lock up.
The shafts have not been compaired side to side at this time.
The tail-cone is not installed.
My guess is a bearing not seated or a missed snap ring.
Any questions or suggestions appereciated(sp)
Wayne

Is the case on the bench or in the vehicle? Neutral on an NP231 ties the front and rear shafts together, so if you have it in the vehicle and the front shaft hooked up, the rear shaft will not turn.

old_man said:

Is the case on the bench or in the vehicle? Neutral on an NP231 ties the front and rear shafts together, so if you have it in the vehicle and the front shaft hooked up, the rear shaft will not turn.

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It,s out on the bench.
The idea was to pull the old 200000 mile unit and replace with a minium of down time.
Wayne

old_man said:

Is the case on the bench or in the vehicle? Neutral on an NP231 ties the front and rear shafts together, so if you have it in the vehicle and the front shaft hooked up, the rear shaft will not turn.

Click to expand...

only if you have an XJ case... My TJ case has true nutral...

sounds like something is out of alignment...
do bolth pumps spin freely by hand?

the tailcone might actually help you via alligning the mainshaft and keeping it from moving from side to side - so install that with a pump and see what happens?


have you called collins Bros?

they probably have some tech help that might be good to talk too...

XJ_ranger said:

only if you have an XJ case... My TJ case has true nutral...

sounds like something is out of alignment...
do bolth pumps spin freely by hand?

the tailcone might actually help you via alligning the mainshaft and keeping it from moving from side to side - so install that with a pump and see what happens?


have you called collins Bros?

they probably have some tech help that might be good to talk too...

Click to expand...

Both pumps spin free.
When the pump is in place on the shaft and the case half is tightened down with the pump tabs in the correct location the shaft will snug up and stop turning.It is a length issue not an alignment issue(I think) almost as if the shaft was too long in one area,a shaft compairson will be done soon.
Wayne

Try throwing on the tail cone and torqueing both yokes down to 150 ft lbs. That helps to align everything up and might solve your problem.

Also are you putting the tabs for the pump on the outside or the inside of the transercase? I made the mistake of putting them on the inside and snapping them off, the tabs should be on the outside of the cover...

Jeepkid8037 said:

Try throwing on the tail cone and torqueing both yokes down to 150 ft lbs. That helps to align everything up and might solve your problem.

Also are you putting the tabs for the pump on the outside or the inside of the transercase? I made the mistake of putting them on the inside and snapping them off, the tabs should be on the outside of the cover...

Click to expand...

I believe we have a winner.Both of us were putting the oil pump on then the cover on top.The cover was never tightened enough(2 bolts) to put any real strain on the pump,but it would lock up the shaft.
Thanks,
Wayne