1) On the end of the axle opposite the motor/gearbox. Punch out the axle pin.
(hammer & punch) (May not be necessary if axle is in two pieces) Note: Must support axle when punching out pin
2) Also, on that end remove wheel bearing, snap ring, and washers. (snap ring pliers) (save & reuse)
3) Disconnect motor plug from controller. This is done by locating the controller compartment (it is on the underside of the cart below the plate where the battery sets. Removing the 4 screws from controller compartment cover. This will expose the controller, then disconnect wire to motor.
4) Disconnect back plate from gearbox cover; 2 nuts / 2 small bolts
5) Slide back cylinder to expose collar & set screw.
6) Unscrew set screw from collar, then remove remaining piece of axle (2.5mm Allen wrench) Note: In older models there is a small ball bearing inset in the axle that must be removed in order to remove the axle. This may be discarded as the ball bearing has been replaced with an updated set screw on new axle assemblies. (If the axle is broken in two this step may not be necessary.)
7) Slide new axle through gearbox with double hole on this end and single hole on far end.
8) From the other end, slide collar over axle. You must align the hole in the gearbox, with the hole in the collar, and the partial hole in the new axle.
9) Screw set screw into collar to attach all three pieces. (2.5mm Allen wrench)
10) Slide axle through cylinder
11) Re-attach back plate to cover of gearbox
12) Plug motor back into controller
13) Re-affix cover over controller compartment
14) Install wheel bearing, washers, and snap ring at other end of axle to center assembly.
15) Installation Complete