L4630 - PTO interlock prevents tractor from starting even with PTO disengaged

Llaves

New member

Equipment
L4630-GST-C with LA853
Jan 17, 2016
21
2
3
Llaves, New Mexico, USA
Went to start the tractor yesterday and the PTO indicator light was on. This was strange as there is nothing mounted to the PTO and I have used the tractor many times since the last implement was taken off. I did the usual jiggling of the lever, also fully engaging and disengaging the lever. No effect. I suspect a mouse/wiring issue. Where is the sensor/switch located? Where does the wiring run?
 

whitetiger

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Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Nov 20, 2011
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Kansas City, KS
Went to start the tractor yesterday and the PTO indicator light was on. This was strange as there is nothing mounted to the PTO and I have used the tractor many times since the last implement was taken off. I did the usual jiggling of the lever, also fully engaging and disengaging the lever. No effect. I suspect a mouse/wiring issue. Where is the sensor/switch located? Where does the wiring run?
The switches are mounted right under the bracket for the PTO lever.
 

whitetiger

Well-known member

Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Nov 20, 2011
1,956
586
113
Kansas City, KS
Is there any way to override the interlock so that I can get it on a trailer to haul to the shop?
Is it not cranking or is it cranking and not starting?
If it is not cranking, you can unplug the small exciter wire from the starter solenoid and jump from the battery cable post to the exciter wire tab. Make sure the transmission is in neutral and preferably have someone setting in the seat depressing the clutch pedal.

If it cranks but will not start, remove the shutoff solenoid from the injection pump and stick a rag into the hole. To shut off the engine, you can use the shutoff lever on the injection pump, it's mounted right next to the throttle arm.
 

Llaves

New member

Equipment
L4630-GST-C with LA853
Jan 17, 2016
21
2
3
Llaves, New Mexico, USA
It's the not-cranking case. The PTO idiot light is on and nothing happens. I'll try as you suggest. That will at least let me get it on the trailer and to the shop where it will be easier to work on.

Thx.
 
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Russell King

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Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
3,208
424
83
Austin, Texas
Is it not cranking or is it cranking and not starting?
If it is not cranking, you can unplug the small exciter wire from the starter solenoid and jump from the battery cable post to the exciter wire tab. Make sure the transmission is in neutral and preferably have someone setting in the seat depressing the clutch pedal.

If it cranks but will not start, remove the shutoff solenoid from the injection pump and stick a rag into the hole. To shut off the engine, you can use the shutoff lever on the injection pump, it's mounted right next to the throttle arm.
To run the key may have to be in the run position but I don’t know for sure
 

Llaves

New member

Equipment
L4630-GST-C with LA853
Jan 17, 2016
21
2
3
Llaves, New Mexico, USA
is this lead what you are referring to as the exciter? Presumably one lead is ground, the other is shorted to the battery to start the tractor.
DSC_0086.JPG
 

Russell King

Well-known member

Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
3,208
424
83
Austin, Texas
is this lead what you are referring to as the exciter? Presumably one lead is ground, the other is shorted to the battery to start the tractor.
View attachment 60997
No. That is the alternator.

Let me find a link to show you how to jump the starter I’ll be right back

See post #2 in this thread
 

Russell King

Well-known member

Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
3,208
424
83
Austin, Texas
Just be careful if you do that, you are bypassing all safety switches and the tractor will start. Be sure you have the tractor in neutral and someone in the tractor seat that knows how to use the brakes and turn it off. Better yet they should know how to get it off of you if something bad does happen.

Jumping between those terminals is a short event so be sure you use something that is easily removed. It will be like turning the key to start and releasing the key when the tractor starts (if that makes sense). Only you and the wire/screwdriver/temporary switch are the key switch instead.

You may want to extend wires long enough to get out of the tractor wheels if you’re doing this alone with no one around to watch out for your well-being.
 

Llaves

New member

Equipment
L4630-GST-C with LA853
Jan 17, 2016
21
2
3
Llaves, New Mexico, USA
These are all very sensible cautions, to which I'll add, this is not a substitute for fixing the tractor in the first place. In my case I'll be doing this solely to be able to get the tractor onto a trailer and into the shop.

Wires long enough to keep you well out of harm's way is a great idea. Even though it's just the solenoid, it still takes a fair amount of current as witnessed by the size of the wire that you disconnected. You'll need decent sized wire to eliminate the voltage loss small wire will present.

I plan to use about a foot or so of 10 ga wire with a spade connector on the starter, then jumper cables connected to the positive terminal of the battery. This will allow me to stand away from the tractor when I touch the jumper cable to the 10ga wire to start the tractor.