727 Pump

[KCbelvedere]

Thoughts on why my torque converter will not spin on freshly rebuilt 727? I have it fully engaged into the pump and then it refuses to turn. I rebuilt the 727 so did I set something up wrong? The center shaft spins and rotates the tail shaft but once engaged with the pump it will not rotate.

 

[dvw]

Either the pump gears are binding or the pump bushing is to tight. Tighten the front band all the way. That'll keep the internals in place. Then pull the pump. Take the pump back apart and check it. test fit the front half on the converter. If the pump bushing was replaced and staked it may have high spots. Trim them with a sharp knife. make sure the pump gears are lubed. Make sure the garter spring didn't come off the front pump seal and jam in the pump. Loosen the band before pump reinstall. Adjust it afterwards.
Doug

 

[451Mopar]

Sounds like a pump problem.
Just make sure the converter is the correct year / spline count for your transmission input shaft.

 

[KCbelvedere]

Sounds like a pump problem.
Just make sure the converter is the correct year / spline count for your transmission input shaft.

Would the converter slide in all the way if the spline count was off?

Either the pump gears are binding or the pump bushing is to tight. Tighten the front band all the way. That'll keep the internals in place. Then pull the pump. Take the pump back apart and check it. test fit the front half on the converter. If the pump bushing was replaced and staked it may have high spots. Trim them with a sharp knife. make sure the pump gears are lubed. Make sure the garter spring didn't come off the front pump seal and jam in the pump. Loosen the band before pump reinstall. Adjust it afterwards.
Doug

Ok, I thought I may need to open it back up as well. It is weird, the converter will not spin at all, not even a slow labored turn. Just full stop.

 

[RemCharger]

You could try spinning the pump with a little screwdriver just to see what's up

 

[KCbelvedere]

Just updating for reference. I pulled the pump and opened it up. When I was looking at the gear set the outer ring looked high in the set so I pulled it out and flipped it and it sat just a hair lower in the case. I didn’t know they were directional but flipping that outer gear set bought the clearance needed when bolted together and spins freely now.

 

[dvw]

Just updating for reference. I pulled the pump and opened it up. When I was looking at the gear set the outer ring looked high in the set so I pulled it out and flipped it and it sat just a hair lower in the case. I didn’t know they were directional but flipping that outer gear set bought the clearance needed when bolted together and spins freely now.

They are not directional.
Doug

 

[KCbelvedere]

I thought I read that as well when I was putting it together. For whatever reason it sat lower once flipped.