CJ750 toolbox

Alternator rotor removal tool by Murray Bowden

I took the alternator rotor off my OHV CJ today. As you will know, the tapped hole in the rotor and the crank are the same so you can't simply wind a bolt in to use as a pusher to get the rotor to break the hold of the taper and fall off. I have listed how I did it and added some photos in an effort to help all the other Changsters out there.

The long cap screw that holds the rotor on seems to go through three threaded sections before it finally holds the rotor in place.

One section is the actual rotor, one is the extreme end of the crank, and the last one is further down the crank.

1. Remove the long cap screw that holds the rotor in place using an 8mm Allen key.

2. Get hold of a 10 x 1.5mm grub screw about 40mm long.

3. Screw that into the rotor and make sure that it goes all the way through the rotor and exits out the bottom and then into the crank. Screw it into the crank by about 10mm.

4. Get a 10mm set screw (that's a bolt that has thread all the way to the head) of about 60mm long. Screw that into the rotor until it will go in no further. The end of that bolt is now touching the end of the grub screw that's already in the end of the crank.

5. Give it a slight turn with a spanner and the taper will be released, letting the rotor drop into your hand. (Make sure that it does drop into your hand and not onto the floor.)

The grub screw going into the rotor before exiting the rotor and screwing into the crank.
The pusher bolt being screwed into the rotor until it touches something solid.
The grub screw is positioned in the crank after the rotor has come off.
All the tools used to get the rotor off with a minimum of effort so no risk of any damage.

I made both the grub screw and the pusher bolt, mainly because I wanted it "right now" and didn't have the right bits.

I cut the threaded section off a 10mm bolt and drilled and tapped the end to screw in a little grub screw. This allows me to use the inhex to wind the 10mm grub screw into position in the crank.

I extended the thread on a 10mm bolt to make the pusher bolt.

The making of the 10mm grub screw. I used a 6mm grub screw in the end of the 10mm grubscrew enable fitting of it rather than just cutting a screw driver slot so that a more positive drive is utilized.