Here are some nice instructions with pictures.
Removing z4 roof motor.
If i use the manual crank and wind the front top motor back 4 turns a i would to close it manually and then press close roof button.
How to replace soft top motor without removing roof.
At around 18 minutes when screwing in the hydraulic line bolts back into the motor tighten these two bolts up to manufacturers spec.
Z4 soft top motor replacement shipkiller and others thanks again for the great write ups.
A replacement motor was a cool 350 plus a new housing and hydraulic repair kit bringing the total to 450.
As noted the numbers on the new motor doesn t match the original motor so just tape your hydraulic lines left right when facing the motor and you won t have any problems.