51 B Wico Mag Rebuild

I bought a new coil and coil bar from the local JD Dealer, but the bar is too wide for my old Wico Housing. Is it OK to machine the new coil bar to the proper width??

I tried using the old coil bar with the new coil and got no spark. I guess there has been a change in technology in the last 40 years?

Any suggestions.

~You could very easily have an original coil, or just as likely it could be an early replacement from years ago.

~On the coil core...If the one from Deere doesn't fit maybe it's from a different model Wico mag. Are you sure the coil is for the correct model of your Wico mag??

~Make sure the coil contact button is in the same place on both coils. The old laminated core should work fine & as long as it isn't all rusted up that probably isn't the reason you aren't getting a spark.

~There are a lot of things that can go wrong with a Wico mag & the coil is just a small part of them.

~Tell us what model of Wico mag you are working with & the coil & coil core part numbers you bought & maybe we can help figure out what's wrong with your mag..

The Wico Model is a XB4001.

I had ran the B in the 4th parade but it shut off after about 45 min., (see 7/5 "JD B Runs then Dies) I could get it started by it would run and quit again. When I took the old coil out, the wires were showing on both sides where the core bar was.

I measured the size of the old unit and the new one and they are similar with the single button in the same place. The only difference is the lenght of the clad wire. The old one came out the right hand side and went to the points screw. The only way I can get the new one to reach that point is to turn the coil around. Would that make a difference? The old coil core bar would fit the hole in the coil, but with the wrap around legs it made the new unit stick too far out, and the cover would not go back on.

Jerome

The Wico on the 51 B that I have is a XB4001, which I found out today from Carl and K&K is the Battery Distributor. The parts I bought from the local JD Dealer were for the Mag, not the Distributor, returned them today and ordered the correct parts from K&K. Also got the condensor and the Rotor. Carl faxed me a copy of the parts break down and they match. Yes I have the Reisiter Ballast on the right side and all the parts match up this time. Hopefully we have the problem solved.

Carl explained also that JD only offered the battery distributor in 51 and 52 and only sold a few of them, parts seem to be hard to find but K&K had them.

I'll let you know if this solves the overheating coil problem experienced during the July 4th parade.

Thanks for all your help.

Jerome

The tractor is still 6V. Would the overheating coil also cause the resistor to burn up??

Everything was running well until it had ran for 45 min in the hot sun. Even when I got it home, and let it sit for an hour or so, it started right up, though I did not let it run for that long again.

Thanks for your continued support and help.

Jerome

In any event, no you can not build a new coil bar and have it work right, unless you use the replacement bar you bought as the 'core' for your machining efforts. They are made of laminated high silicon steel for a reason and that reason is to transfer magnetic flux without too much loss due to eddy currents (electricity) being induced into the steel. The laminations make the circuit for these currents very short and thus lower the losses. Make the bar out of solid steel and your spark strength will suffer. Further, the laminations are insulated from one another via special varnish - got any?