Dismantling an ML RF4 magneto

[jr2766]

Can anyone advise the correct sequence to dismantle the above magneto which requires bearing replacement. I've never run into one of these before.
Jim
Perth Australia

[Jack in the Box]

Jim,

I have recently dismantled and reassembled an ML RF4 to change the smaller spur gear. Unless anyone beats me to it I'll share the process I used later today. The reassembled magneto is working well at present.

Alan

[Jack in the Box]

Jim,

I've just dismantled my spare ML RF4 as follows:

I am assuming that the magneto is out of the car and on your bench. My convention is to call the driven end the front as it would be in the car.

1} remove 2 nuts at rear retaining Bakelite distributor cap and remove cap.

2) rotate leaf spring below this and remove the cover revealing the points.

3} slide the points and advance/retard lever rearwards off shaft.

4) undo the bolt at the rear retaining the cam that opens the points. You may need to clamp the drive coupling at the front to do this.

5) slide the cam off the shaft

6) unscrew 2 rear bolts holding the Bakelite distributor to the large upper spur gear. The central carbon brush is spring loaded so remove the distributor slowly.

7) slide the large, upper spur gear off to the rear

8) remove 4 horizontal screws at the front and withdraw the main shaft forwards along with the bearing housing. This should reveal the ball bearing race.

9) with the main shaft removed you will need to undo the nut retaining the drive coupling to be able to remove the bearing from the shaft. The coupling is driven via a Woodruffe key.

I hope I haven't missed anything and that others will comment on what I've said. I have read about the need to remagnetise following disassembly, but (touch wood) mine seems fine.

Good luck. Alan

[Robert Foreman]

When dismantling you can leave the rotor and large gear in place, everything else that Alan has said is sound. 
You may need to invest in a magneto bearing puller to remove the inner races.
   Also note any shims used to take up the end float.

[jr2766]

Many thanks Alan and Robert. I think I am clear on the procedure - removal of the armature was the big mystery which you have covered
Jim