1950 Cub won't start

[amtrac]

Mowed for an hour and a half today with my Cub. Shut it off outside the barn to move another tractor out. Ten minutes later the Cub refused to start. Plenty of gas, but no spark that I can detect at the plug wires at the distributor. The coil is too hot to touch. Is this my problem?? Otherwise, the engine fires right up when it is cold and runs great the whole time I am using it. Just don't stall out or she will sit in the field overnight. I just rebuilt the engine last winter, but the problem existed before that. Same coil, same points & distributor. What should I be looking for?

 

[old]

Is the coil so hot that if you spit on it your spit steams away if yes good chance it is the coil going bad. If it will start after the coil has cool down another indication it is going bad

 

[Janicholson]

Yup. Jim

 

[amtrac]

Well Old, I fergot to spit on her. But my hand came off real quick when I felt up the coil. It did start right up after sitting in the shade for about an hour. Felt the coil this time and it had cooled down to maybe just warm. Maybe get a new coil and try it?? From the looks of it, the coil may be original. 72 years old. When I got the tractor about 7 years ago, It had one of those 8V batteries in it and I changed it back to 6V. Could 8V damage a coil? Thanks, Ron

 

[old]

Yes 8 volts could cause the coil to go bad faster then a 6 volt battery would. It starting back up after the coil had cooled down is a good indicator that the coil is going out. By the way they do not make 8 volt coils that I know of

 

[amtrac]

Nope, I never heard tell of one either. Guess I'll be looking around for another coil.. Thanks a lot. Confirmed my suspicions. Ron

 

[John T]

Typically a coil (with engine running) can run WARM but NOT so hot you cant keep your hand on it. If one were to use a 6 volt coil on a 12 volt tractor with no ballast resistor NOW THAT WOULD RUN REAL REAL HOT and eventually maybe even burn it up ..........

If you have the correct coil and or coil plus ballast so thats NOT the cause of no spark, work my Troubleshooting procedure to help find the problem using no more than your eyes n ears maybe a 6/12 volt test light EASY PEASEY

NOTE so often the problem is the POINTS burned or pitted or carboned up or mis gapped TRY THAT FIRST

John T
John Ts Ignition Troubleshooting

 

[gene bender]

i know two tractors that use 8v batts with no coil problem and have been on 8v for yrs