BX25 cuts out when HST is engaged...

maclean

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Equipment
BX25D
Jun 25, 2014
242
3
0
Lowell, Or
2014 Kubota BX25D-2 - 720 hrs. Starts just fine. When we press the forward petal on the HST the tractor starts to cut out and dies if we continue to press the petal.

If we disconnect the fuel cutoff on top of the engine it runs just fine.

The seat switch is already jumpered. The PTO switch is unscrewed and taped and cable tied shut. Replaced both fuel filters. Diesel is clean and no obstructions from the tank. Checked the oil and hydraulic fluid levels and they are fine. Same with radiator fluid. All the fuses are intact.

Anyone have a wiring diagram or know what's in series with the fuel cutoff?

-Mac
 

85Hokie

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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
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I would check the seat switch one more time!;):)
 

maclean

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Equipment
BX25D
Jun 25, 2014
242
3
0
Lowell, Or
I would check the seat switch one more time!;):)
Verified with a multimeter - have continuity from the back side of the plug to the other side...checked three times...absolutely certain this is not the issue.

I wired out the seat safety switch a long time ago...I don't weight enough to keep the tractor running with the switches plugged in.
 

maclean

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Equipment
BX25D
Jun 25, 2014
242
3
0
Lowell, Or
Likely a stupid question, but the brake is not on is it?

Sent from my LG-H812 using Tapatalk
Nope...didn't think there was a cut off switch on the brake...sure wish there was...someone clicked the emeregency brake down one click a while back and we drove it for an afternoon with no idea the brake was partially on...didn't cut out then and we have no more brake...and thank you to Kubota for putting it inside the transmission. We already pulled the engine to replace the transmission fan once...and the new one is down a fin and this after purchasing and installing both BroTek skid plates.

-Mac
 

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
I just checked the service manual for a wiring diagram, there isn't one for this model.
 
Last edited:

maclean

New member

Equipment
BX25D
Jun 25, 2014
242
3
0
Lowell, Or
I just checked the service manual for a wiring diagram, there isn't one for this model.
That's a big shame. I removed the tailights when we disassembled the tractor to fix the HST fan and I have no idea which connectors plug into which...have all the wires taped off for now...

That and no wiring diagram doesn't exactly help me figure out what's tripping the fuel cut off...is there a troubleshooting section in the service manual that lists causes for triggering fuel cut off?

-Mac
 

North Idaho Wolfman

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You do know that there are 2 switches for the seat, I'm betting the second switch is bad or maladjusted. ;)

The other part that could be an issue would be the OPC timer.
 

maclean

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Equipment
BX25D
Jun 25, 2014
242
3
0
Lowell, Or

maclean

New member

Equipment
BX25D
Jun 25, 2014
242
3
0
Lowell, Or
Ok...pretty sure it is the OPC Timer...



The big dent in the side is a clue...I didn't test it.

So...according to the wiring diagrams...how do I wire it out...I jumpered pins 2-3 and 4-5 together, and that didn't work...do 4-5 need jumpered and ran to ground?

More pictures...since I went through the trouble to upload...



I need to jumper out the PTO switch too...anyone know which pins to connect on that one? The tape I put on it melted off this afternoon...and the cable ties slipped off.



The tractor and some implements...



Under the hood...note the white connector over the fuel relay in the bottom right corner (almost center, really...) is what you DISCONNECT to keep the tractor running and RECONNECT to turn it off once you are done. And the Dorman start switch and fuse I installed for an emergency bypass start (which I hate to say I use more and more...) I put in under the hood for a couple of reasons...keep it out of sight and encourage me to fix issues.

 

maclean

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Equipment
BX25D
Jun 25, 2014
242
3
0
Lowell, Or
OK...confirmed...on the back of the tractor...right hand side under the fender you'll find the timer relay. I made a jumper out of tinned 16 g wire and shoved it into the contacts...connect the red and the red/white cables and you will bypass the timer.

-Mac
 

North Idaho Wolfman

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Sandpoint, ID
WOW!!

You have done one serious job of making your tractor as unsafe and dangerous as you could have.


WHY?
 

Tooljunkie

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L1501,home built carry all, mini plow blade.
May 13, 2014
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Lac Du Bonnet, Manitoba,Canada
Something has to be said about safety switches, they are a nuisance. Various ones can be bypassed to lessen certain incinveniences, but bypassing everything that starts/stops the machine from operators seat is risky. Not to mention that if someone that is unaware of this situation could be put in a bad situation.

My small riding mower has safety switches, all intact. Inconvenient, but all kinds of people run it.

Your machine,your choice.you get get hurt thats one thing, someone else-thats a different story.
 

maclean

New member

Equipment
BX25D
Jun 25, 2014
242
3
0
Lowell, Or
WOW!!

You have done one serious job of making your tractor as unsafe and dangerous as you could have.


WHY?
Because this tractor spends a whole lot of time trying not to kill me. A lot of time. If Kubota would use higher quality switches and mechanisms that did not fail regularly then I would leave them on the tractor.

I have lost HOURS and even DAYS trying to get this tractor to either start or move forward because of this equipment.

The neutral safety switch for example...the PTO lever has a bar that engages the switch...that bar bent (probably this winter when clay picked up by the tires and packed into the wheel wells and started extruding out of the controls...makes shifting out of 4x4 and low/high impossible until you spend 2-3 hours with a pressure washer hosing it all out. I think I solved that issue by installing 3" wheel spacers...but it is a horrible design by Kubota to have all of those wires and levers exposed to anything picked up by the tires in the wheel wells. Look at any of the bigger tractors and they don't have the same issue.

The seat switches were designed for fat, overweight people...makes sense...that's most of us, and I get it. I had to modify my motorcycle suspension because 130 lbs didn't budge the springs. And on this Kubota tractor every time I would hit any sort of a bump the engine would cut out. Since I wired out the seat switches...when the OPC timer broke (another item inside a fender well) it made sense to jumper it out rather than replace it.

I installed a starter bypass switch...like many of us have done...because I have been stuck over and over again trying to find which combination of safety switches are tripped and preventing me from using the tractor.

I am all for safety equipment that works. The ROPs is still on my tractor. I wear the seat belt regularly. And if the rest of the crap on this tractor worked...and worked consistently...then I would leave it alone.

-Mac
 

sheepfarmer

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FWIW my dealer came out and fixed one of the seat safety switches on mine with a piece of cardboard inside the seat so that my 133 lbs would reliably depress it and allow it to behave as designed. I don't have any hints for the others though.
 

rentthis

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Yesterday, I had exactly the same problem with an L-45. I jumped the switch and it didn't work. I check under the seat and found a plug connection to the seat switch wires farther down the line. It was unplugged. Problem solved.