Magneto Charging

[Bruner]

Hello I have a fm j4a11 mag it is on a wisconsin ac4 I am not getting much of a spark I believe it has 3 magnets only 1 has very weak pull and the others have none when touching with a screw driver. I would like to know if this is the cause or not. I would also like to know the cost associated with getting the magnets charged.
Thanks
Nate

[Bruner]

I was searching in the manual and it looks like I am supposed to have a wico a-4 base mount magneto does anyone know where I can get one cheap around $50.00
Thanks
Nate

[Dempster]

3 magnets ? The magnetic rotor should only have 2 poles north and south. Are the ends busted off with the bar magnets inside showing? If so you need another magnet rotor or another mag. Check out the FM-J4 cross sections on this link and the Fairbanks Morse - Magneto Fundamentals.

http://www.oldengine.org/members/die...s/MagData2.htm

I'll look tomorrow if have a Wico or Fairbanks Morse mag for you engine. You can run either one Wisconsin used on a while then another or a mag shop sold someone another for a replacement. Originally depending on the age your AC4 engine might have came with a long obsolete Wico LD4 or replaced later by Wico A4 or later Wico C4 or last Wico XH4. Some parts are still available for Wico A4 & C4 and most everything for XH4 they are still making it new again. The FM J was replaced by same looking mag a later FM X4.

[Bruner]

sorry there must only be two but I was only getting pull off one. I am new to the whole magneto thing are you saying that I can use any of these mags or can you help me with a few different ones I can use. Not restoring just want to get it running again.
Thanks for any help.
nate

[Dempster]

I'd say just trying to fix the mag you have now then. I work on them and have a magnet charger too that recharge is something always done on a complete overhaul of a mag. Checked Wico manual and they listed these for Wisconsin AC4 and couple other engines too. Wico A-241F, C-241F & XH-241. Not sure I have the correct drive cup to build one of the Wico or the exact one as have several base mount Wico and FM parts mags would have to look through.