Fairbanks 6hp mag gear

[Matt S]

Does anyone know how many teeth are used for a late 20's 6hp fairbanks? I have straight cut gears. It originally came with a "R" type mag. But I recently aquired a "J" type And was wanting to fit that to it. I got the engine with no mag or gear. I was wondering as well if there is a difference in shaft hights from the R to the J. Thanks for any help on this!

[joe strube]

I HAVE A COMPLETE MAGENTOR FOR THIS ENGINE. IT IS HOT.IT WILL TRADE IT FOR A MAGENTO FOR A 8CYCLE AEROMATOR THAt i have or take 300.00 joe in charlotte n c

[Tilinghast]

Matt,
The mags are interchangeable assuming the "J" you have is a base mount. Do you need the number of teeth on the mag gear ?? I have a mag with one on it but someone else may know the number before I can get out the mag and count them.
Dave.

[Matt S]

Yes, It is a base mount. I just have no idea how many teeth should be on the mag gear. Thanks!

[NAMPeters]

The mag turns at half crankshaft speed so count the number of crank gear teeth and then multiply by two.

[KidDynamo]

You might want to post a photo of your J mag and base and post its full model number as not all J base mount mags are created equal. When I get a chance, I'll see if I can find the shaft height.

[Tilinghast]

Matt,
My mag gear has 35 teeth.
Dave.

[Matt S]

Nice, Thanks, I'm going to the shop tonight and I'm going to count my crank gears and do the math.

[David Babcock]

Your magneto gear should be the same as your crank gear. Db.

[Dempster]

All base mount mags are either a standard 35 mm or 45 mm shaft height, center of shaft to bottom edge of mag housing. Your FM-J1A2 for a FM engine should be a standard 35mm housing with special adapter plate B2561A bolted underneath it for about a 40mm shaft height. FMJ1A2 or FMX1A2 with that plate were later replacements for the R 1 cylinder mag. If yours doesn't have that adapter plate it isn't going to work. The link below shows a FMX1A2 with that special mounting adapter plate under it.

http://www.oldengine.org/members/die...etos/FMSS3.htm

http://www.oldengine.org/members/die.../PetrolMag.htm

[Dempster]

Several vendor sponsors on this site sell new gears and would think they should know which one you need.

[NAMPeters]

Originally Posted by David Babcock

Your magneto gear should be the same as your crank gear. Db.

Oooops, Db is correct, I had the cam gear in mind.

[Dempster]

Another image of the FM-X1A2 from a 1951 brochure.

[IMG][/IMG]

http://img188.imageshack.us/img188/3...1a2magneto.jpg