Huntmaster auto advance unit

[roger.strode]

Have removed the unit - went to refit it but would not properly engage. Unit/magneto all new 7000 miles ago. Any ideas on why it will not properly engage?

[Simon.Gardiner]

The long retaining nut thingy that is also an extractor needs to be wound fully in so the extractor threads have gone fully through the plate?
(And I think those might be left-hand threads so they've got to be 'unscrewed' to go through properly?)

Not 100% sure about that as my unit is carefully stored (as in buried) somewhere so I can't check but I know I've had trouble with that before now.

SG

[Mick D]

Hi

I think Simon has it, the central nut has to be wound 'in' so as the internal extractor is disengaged, (wind the nut clockwise until all becomes free and easy).

Regards Mick

[roger.strode]

Thanks for the helpful comments! I’ve turned the hex head clockwise which fully releases the (left hand thread) threaded piece. I’ve tried to fit the unit onto the magneto taper BUT the fibre cog does not fully register and projects some way beyond the meshing steel cog. Any attempt to tighten the threaded piece soon “fully” jams up. Any advice would be very much appreciated!

[Simon.Gardiner]

I'm finding this confusing....

Roger, with the threaded piece out of the unit completely (ie with nothing to secure it), will the unit seat on the mag taper and mesh properly?

SG

[roger.strode]

Thanks Simon I’ll check tomorrow and reply. Roger

[Mick D]

Hi

If the retaining nut assy is free to turn when you have the unit in your hand then it should fit. When you offer up the unit to the magneto taper you need to wind the retaining nut in to engage the taper, (just finger tight to allow you to set the timing). If you can't wind the AR onto the mag taper then it suggests the thread has suffered some damage during removal, have a close look at the thread in the AR and on the mag.

Regards Mick

[roger.strode]

Hi Simon have inserted the unit minus the threaded piece. The fibre pinion “appears” to project beyond the steel pinion but on measuring with micrometer it is 1.5mm so should be ok! I’ve managed to make a complete pigs ear of removing the metal threaded piece and damaged it’s thread!!! I will now mull over what to do! with grateful thanks Roger