Re: Alternator rotor and stator gap

Perhaps loosen off the 3x nuts and remove the stator... fit a strip of 8mm thick card or plastic around the rotor then refit the stator and tighten the nuts and remove the strip...There is some play in the stator fixing holes relative to the studs,

(If the stator simply goes back on just the same then the alloy fixing hub might need to be carefully expanded on the tight side to allow the stator to move back to the right a touch. You could either scrape it or using a rotary stone?) Please note I don't know if the single cylinder engine uses an alloy mounting hub like the heavy twins....

Les

AS Les said, but using feeler gauges, inserting them in 3 different positions around the circumference; more accurate. 8mm card would be a trifle too thick....

Previously aled_corps wrote:

When putting together the alternator on my Norton, I understand that there should be a 8 thou gap between the rotor magnet and the stator. I have a gap close to 8 thou most of the way round, but on two points there's no gap at all, and seen as the stator is sitting nicely in it's casing, I can't see how I adjust or move it at all. Please see image with blue arrows pointing to the parts that touch.

Is there a trick to how you make this fit? can any part of the stator be filed down either inside or out?

Thanks

Aled

Hi Aled, Usually the stator mounting holes are a clearance size for 5/16 inch whilst the mounting studs are 1/4 inch so here is the trick. Slacken the nuts slightly and on the opposite side of the stator to where the clearance is too little strike the stator with a hide or fibre mallet. Then check clearances all round. You may have to repeat this process a few times but eventually you will get there. Obviously it's better to not strike a stator coil so you may have to press a piece of red fibre or soft metal against the stator and then strike that hard but carefully. It's a common adjustment on the twins. Regards, Howard