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JJSmitches
12-09-2005, 04:22 PM
My brother-in-law is having problems installing the transmission in my Chevelle. He is working on the car in his automotive class and his instructor thinks there is a problem with the pump.

The input shaft doesnt seem to turn at all. Any reason that it shouldnt spin freely?

They removed the pump and loosened the bolts holding it together, then the input shaft spins freely. However, tightening everything back up again makes the input shaft unable to turn.

New 700r4

If the trans gear selector is in the wrong position will it cause this?
Operator error?
Problems during manufacturing?
Please help

Sorry if I have used incorrect terminolgy, etc. I have never done anything with transmissions.

myclone
12-09-2005, 05:21 PM
Make absolutely sure he's trying to turn the input shaft and NOT the stator support. The input shaft is the smaller splined piece that is surrounded by another splined piece (stator support) down by the pump.

If youre turning the correct piece you will feel some resistance since the input drum is splined into a bunch of other stuff internally. If the trans is a fresh rebuild with new bushings and clutches it can be pretty tough to turn the input shaft but by no means should it be impossible. If the trans was rebuilt then the bushings in the stator support that in input shaft ride on are usually tight and require a little work with some fine grit emory paper to open the clearances up slightly since new bushings usually bind the input shaft a little. Also, if the bushings are installed in the stator support in any way other than perfect the binding will be even worse (aka if they were just hammered in place without the proper bushing installation driver youre pretty much screwed).

If the trans is used and has some miles on it then something isnt right if the input shaft wont turn without loosening the pump. You should still feel a fair amount of resistance but it should turn by hand with a little grunting.

Gear selector position doesnt matter since there is no fluid pressure to engage any of the frictions.

HTH.