JD 4200 dies when i put it in gear. One of many problems but the most important now.

[BradleyJD4200]

My JD 4200 started a new problem today, it starts(after i ground out the thermistor) and runs fine. But when i try to put it in gear, or engage pto it shuts off.
I have added 2gl of hyd, jumpered and by-passed the seat switch, and punched the fuse box. Surprisingly none of these things worked. Its broke down a long ways away from the house up in the woods of course.
Any information would really be appreciated.

 

[Storm56]

I have a feeling you are going to find the answer in those safety swithces, they are all tied together forwards and backwards so to speak.

 

[RoyJackson]

There's also a PTO safety switch and, IIRC, a neutral safety switch. Either of these should prevent the starter from cranking though.
Since the tractor is in the woods, I'd look underneath for any wires that may have caught on brush.
Anyway to tow the machine out of the woods?

 

[BradleyJD4200]

Yeah, i've got an old ditch witch with four wheel, a beast. I'm gonna do that at least it will be convenient to troubleshoot.
Do you know anyway of bypassing all those safety systems? scary notion, but it would be nice to have going for the summer. thanks for replying

 

[dfkrug]

Do you know anyway of bypassing all those safety systems?

I put jumpers on the seat, PTO, and HST pedal interlock switches. There is also a brake safety switch.
It sounds like you have a gear trans, so I can see there also being a neutral safety switch. HST
does not have that. You may also have a foot clutch switch. Some interlocks also use a relay. You
need to check your wiring diagram.

As the tractor ages, most owners will eventually have safety switch problems.