Hitchcocks Forum

Hi all, Would any one know how to remove the advance unit from a Lucas SR1 magneto, I need to remove the idler pinion, I have loosened the bolt and removed the u shaped washer and tried a puller on it (not to much force as I don't want to break anything) but it will not budge. I may also have to replace the idler pinion, can this be done without stripping the engine. Clive.

I haven't stripped an auto-advance unit, but the idler pinions simply pull off their spindles. If they're not badly worn you can fit new bronze bushes.



As for the auto-advance unit centre, it might well be hard to shift if it has been sat on the magneto shaft for the last 50 years, try a bit of heat to expand it and/or a sharp tap with a hammer and drift on a non-moving part to break the taper. If the magneto pinion part of the mechanism is badly worn, you might be able to get a new idler pinion machined to take the A/R unit centre.



http://imgp1.en.makepolo.net/o/296/129/ ... a77d3f.jpg



A.

The AA unit is self extracting: undo the nut and it pulls itself free of the taper.

Thank you Tim NZ, it was lock tightened on so was harder to remove and I see that our hosts sell a tool for removing the idler spindle. Thank you all for your help. Clive