H question for teddy52food

wico x mag that has a miss fire on one side. We rebuilt the engine and it now has a miss fire. the miss does not follow the plug
and we installed new wires and cap and rotor and points. The valve lash is good and engine has been bored with all new parts. Now
on the mag we converted the governor drive to run wico x with 25 degree cup and the only thing that i see that might be a problem
is some rust on the laminated steel plates inside the mag. It fires on one cylinder and will start and run. Could this be our
problem?

Did you check for spark from the mag? Any play in the bushing by the points? Cam that opens the points worn? Try gapping the points closer or farther. If it fires on one the coil & condenser are good.

I ll check this out soon, and get back to you thanks. any thoughts on the rusty parts in the mag?

Rust on the outside shouldn't bother but you don't want any on the coil core where it mates to the other part what ever it is called.

No, that bit o rust is not the problem.

If you remove the mag, rotate the shaft 1/2 a turn & reinstall the mag switching the top wire to the bottom & bottom wire to top, does the cylinder that runs move to the other side of the tractor?

If yes, I suspect a rotor cap or both mix up.

What you say indicates the mag is making good spark or it would not start on just one cylinder. It sounds as though you MAY have a cap & rotor that don't match your application. The X mag (in other applications) used a single arm rotor but the JD cap & rotor was different! When you look into the open cap, the number 1 plug wire should go in the top port. The brass post inside the cap which the rotor passes the #1 spark to would be at about 11 o-clock.

The internal brass post for the number 2 port (the bottom one) would be at about 7 o-clock which is only 90? from the upper one.

The correct ROTOR should have two arms on it and those too should be 90? apart! This way the leading arm delivers the spark to the top post of the cap and when the mag shaft rotates 1/2 a turn to deliver the spark to #2, the lagging arm (90? behind the first) plus the 90? from post to post gives the spark to the engine 180? after the first spark.

If the posts inside the cap are only 90? apart you have to have the 2 arm rotor or you only get spark on one side. If the posts inside the cap are 180? apart (from some other 2 cylinder application) only then can you use a single arm rotor.

I'm thinking you either have a rotor/cap parts mix up or one wire is badly pinched or shorting to ground in the spark plug wire conduit! Try a wire outside of the conduit & plug cover on the side that doesn't fire.

Hope that helps.