TC 35 starting issue

WAYCAY30 · Sep 4, 2013

I have had to by pass the solenoid just to get the fuel pump to come on to crank. Is there any reason why this would be happening? All relays have been checked and working.

kydick · Sep 4, 2013

i have 3930 new holland. last year it would not start. tried a new ignition switch a new new fuel solenoid. didnt help. rerouted some wires and got it to run. kept checking it out. had some bad diodes in the dashboard. changed them and havent had no more touble with starting.

jinman · Sep 5, 2013

WAYCAY30 said:
I have had to by pass the solenoid just to get the fuel pump to come on to crank. Is there any reason why this would be happening? All relays have been checked and working.

I don't understand what you mean by bypassing the solenoid. Which solenoid: starter solenoid or fuel cutoff solenoid? Do you mean hot wiring the fuel cutoff solenoid with 12 volts? There is no electric fuel pump on your tractor, it's mechanical and runs anytime the engine is running. My guess is that you mean you have to hotwire the fuel cutoff solenoid so it allows fuel to go to the injector pump. If that works, then the most likely problem is your seat switch is defective. With the transmission in neutral, you should be able to pull up on the parking brake handle to get the engine to start, but it will die when you release the handle. That's a sure sign the seat switch is defective. You can bypass the seat switch by removing the connector and putting a jumper between the pins in the plug on the wire coming to the bottom of the seat platform.

WAYCAY30 · Sep 5, 2013

Yes, Jim I have a toggle switch that I have to turn on to crank and turn off when I turn the tractor off. So it is the fuel shutoff.

jinman · Sep 5, 2013

If your seat switch is working fine, then it's probably the operator safety module. That's a fancy word for an encapsulated module that does about the same thing as a relay. However NH wants about $245 for that module. They are holding you up without a gun. It's not the dealer's doin' it to you, but New Holland and probably Shibaura too. Your switch solution is a good backup, but make sure you pulled 12 volts from a line with a fuse in it. If that fuel solenoid ever shorts out, you'd have a fire on your hands in an unfused circuit. If nothing else, buy an inline fuse from any parts store and put it in the wire. 5 amps should be plenty.