4020 LP PERTRONIX IGN TROUBLESHOOT

[TIMAR]

Just put the kit on a 1970 model and am having problems. Is there a resistor somewhere? Voltmeter says there is 11.8V to the coil with the key on. Tractor will fire while engaging the starter but dies as soon as key is released. Someone told me to run a jumper wire to the coil? Or to the Pertronix red wire?
 

[S.C.]

I installed one of those ignitors on a 4010. Not sure if a late model 4020 gas is similar. A 4010 used a 6 volt coil and was 12 volt positive ground. There is a resistor on the ignition switch that drops the voltage to the coil to around 6 volts when the key is in the run position. When the key is in the start position this resistor is bypassed and 12 volts is at the 6 volt coil to make a hotter spark while cranking. Easier starting was the idea behind this. I removed the resistor and used a bolt for a jumper so there is 12 volts at the coil when cranking and running. Also used a 12 volt coil. This may be why yours dies when the key is released to the run position if you changed the coil to a 12 volt. There are others on here that know a lot more than I do but this may get you headed in the right direction. Also that was the best improvement I've made on that tractor besides switching to a Zenith carb. You won't be disappointed after you get it lined out. Be sure and check the timing also.
 

[John T]

Im not familiar with New Generation but if the tractor uses a 6 volt coil and has a series ballast resistor and a working ballast by pass if the elec switch is working and conducting current (like if it had points and they were closed) with the Ign on Id expect to see around 6 volts on the coils input and 0 on its output (To distributor). If youre seeing 12 on the coils input with the ign on look n see what the voltage is on the coils output (to distributor) ??? If its also 12 n stays there the switch isnt closing and conducting coil current as it should normally, its ONLY when it opens the coil fires. A test lamp on the coils output should flash on (switch open) and off (switch closed) if the tractor is cranking over. This assumes its all wired correctly and if it has a ballast its good and NOT bad/open.

John T