TC25 Safety Switches?

   / TC25 Safety Switches? #1  

TORQUIN

Silver Member
Joined
May 22, 2004
Messages
185
Location
Powhatan, Virginia
Tractor
Kubota L3830
I have a TC25 I am working on for a buddy. My tractor is a Kubota, so I am not familiar with this tractor. He started it and got it off the trailer, but by the time he got it to the garage a wire had broken on a safety switch, for range, and it would no longer turn over. Wire broke right where it goes into the switch body. I found that the switch in question costs over 100 bucks so, for now, I bypassed it by connecting the wires for it together. Engine still will not turn over, so I am looking for the rest of the safety switches. I know about the PTO switch, but are there any others, such as on the gear box, clutch, brake, etc.?
I have checked and found all fuses along the right side of the firewall are OK. I do not know if there are fuses anywhere else besides the one beside the starter, in the harness.

Thanks,
Chris
 
   / TC25 Safety Switches? #2  
On my TC which is a hst model, there are switches to make sure the gear is in neutral, brake is set, PTO is off and your butt is in the seat. Seat switch is easy enough to defeat with a jumper.
 
   / TC25 Safety Switches?
  • Thread Starter
#3  
Forgot to mention, this machine does not have shuttle shift, and is a geared machine with 3 ranges.
I looked for the seat switch, but have not seen any wires going to the seat. When trying to start it, I did sit in the seat in case there is a switch in there. I will continue to look for the seat switch.

Thanks,
Chris
 
   / TC25 Safety Switches? #4  
If the TC25 is like my TC40DA, the safety switch system turns off the fuel solenoid so the tractor will still turn over, just not start. If it won't turn over, your problem may be elsewhere, like the ignition switch or a fuse.
 
   / TC25 Safety Switches? #5  
Behind LR wheel....mid pto switch, gear range switch, rear pto switch.
 
   / TC25 Safety Switches?
  • Thread Starter
#6  
I am not getting power to the switches on the left side. I'm guessing that the mid PTO switch is the one factory bypassed, since I don't have one of those. Mid-PTO seems to be the last one in the line, since it goes straight to ground from the connector. Haven't pulled the harness sheath apart to find out which is the first one in the line yet. Trying to avoid that, if possible. All fuses one right side of firewall have been checked again, and are fine.
Starts and runs fine if I bypass the starter circuit with a remote starter switch, so the fuel solenoid is working fine.
Anyone got a wiring diagram?
20240204_165922.jpg

Thanks,
Chris
 
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   / TC25 Safety Switches? #7  
cant remember too much about it now but several years ago my 3930 would not start. there was a diode behind the instrument panel that had to be replaced
 
   / TC25 Safety Switches? #8  
I hope these help.
 

Attachments

  • 25 Series Electrical Schematic.pdf
    897.8 KB · Views: 63
  • 25 Series Start Circuit.pdf
    485.9 KB · Views: 45
   / TC25 Safety Switches?
  • Thread Starter
#9  
I hope these help.
Interesting. I do not have an accessory position in the ignition switch of this tractor. Also,I have to assume that the "Glow Plug Heat" position, 3, is also the run position, for the switch.

Thanks so much for the diagrams. They confirm what I am seeing on the tractor, no glow plug timer, but make me wonder about the actual operational details of the glow plugs (another issue I am working on).

Thanks,
Chris
 
   / TC25 Safety Switches? #10  
The OEM ignition switch on my TC33D was a pretty flimsy design and failed. I replaced it with a more robust one from NAPA. I wonder if yours was replaced at some time?

TC33D Glow Plug Problem Fixed

There also could be some variation withing the TC25 series so the schematic which supplied might not be 100% accurate. How many wires do you have connecting to your switch?
 
 
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