39 B John Deere running problem

[shomfeld]

Last summer I dicided to take my 39 B on a tractor ride. Before the ride I put new plugs in and cleand the setlment bowl and found out it was clean also I took the bottom bowl off the carb and found it had rust in it so I cleaned and put fresh gas in. It fired and ran fine but I soon found out it did not have the speed to keep up. I found a overdive and instaled it and took it out on another ride. I had the speed now but 1 hr in the ride when I got backed up in trafic and started to use the clutch it staring to cut out. I found that I could leave the cluch in and the motor would some times fire back up. It seemed to run fine intill it was warmed up and the motor was not under a load. When It would died we would pull start it and it would fire right up so I opened the bottom of carb and found it was clean and had a good flow of fuel. Ok now do I have a fuel problem or a weak mag Thanks

 

[PopinJohn]

From what you said, it sounds like a condenser going bad in the magneto, or the coil is shorting out internally when it gets hot. PJ

 

[BushogPapa]

Which plugs are you using..??
The wrong plugs can foul quickly..
If you suspect ignition, narrowing the plug gap should improve things...one way to help find the problem..

Are you using copper-core plug wires..?

I have gone to a set of spiral-wound "Super-Stock"
high-performance wires that sure made a difference in my 2-cylinders..
One set will do 4 JD tractors..!!

Ron..