wiper motor, assembly issue

[rickcsvdubs]

hey everyone happy 4th! the wife took a nap so i figured i would mess with my wipers again. i have a 63 that i am converting to 12v. the last step is the wipers. i had a bosch motor originally. i purchased a SWF motor with assembly and installed the WW 12v armature. when i have the motor off the assembly and test it the motor spins freely. when installed on the assembly it makes 3/4 turn and stops. i tried the original assembly from the car. same thing. i had a 68 motor laying around so i made some mods to the 63 arm and tested it and it works. full revolutions continuously. Can anyone out there see an issue with my original 6v to 12v setup that would not allow it to freely turn 360 degrees? when the motor is attached to both assemblies I can feel a spot where the arms get stuck. when i move them by hand i can feel the "pop" thank you in advance for any light that can be shed on this issue.

[rickcsvdubs]

so after many attempts i cannot get my wiper motor to turn freely when on the assembly. i was going to use the 68 motor on my original assembly but realized since this is a 63 the park position would be incorrect. i am stuck at this point.

here is the story: i originally had a 6v Bosch setup. i purchased a swf placed the Wolfsburg west 12v armature into the swf motor and went to test. it will rotate to 3/4 of a turn and get stuck. i can still hear the motor. i quickly turn it off. i removed all the old grease and re-greased the motor. same results. i backed off the motor nut from the assembly to see if it was tightened down too much. same issue. i was going to use the 68 (swf) motor on the original assembly but it parks on the left not on the right as my 63 would. does anyone have an insight as to why the 66 down motor will not turn 360 degrees? when i turn the motor by hand i can feel resistance at the same spot each time. when it is attached to the assembly if i rotate it by hand it can feel the motor freely turn until it hits one spot and it it pops out of that spot. broken internal gear/spline?? any help is greatly appreciated!!