Kubota L48 Engine Won't Turn Over

[Richard Maddox]

We use a Kubota L48 front end loader with back hoe attachment at my job site. Recently an operator was pulling limbs from a debris pile, operating too fast, and got a log jammed under one of the rear wheels. He claimed the wheel was spinning without his foot on the traction pedal, and he shoved the range select lever into neutral to stop the wheel from spinning. After he did this the machine cut off and will not restart. Turning the key switch forward will give dash indicator lights, but the fuel cutoff solenoid will not kick off and the motor will not turn over. What are the Ohm readings for the safety switches supposed to read? I tried a jumper wire on the forward/reverse traction safety switch and the seat safety switch to see if either malfunctioned when the incident occurred, to no effect. No Ohm reading from either as well. Any suggestions?

 

[Billdog350]

It sure sounds like the HST pedal got jammed and that's triggering the safety switch at the HST to prevent the machine from restarting. Find out why the HST pedal isn't centering (stick or debris jammed in there? Centering mechanism broken?) and that will solve your issue.

 

[Richard Maddox]

Thanks for the quick reply. The pedal is centering and the plunger on the safety switch is not being pressed upon in a way that would trigger the switch. I Ohmed the switch with it depressed and did not get it to Ohm out. Think I might be on the right track as far as replacing the safety switch?

 

[Billdog350]

I would think the safety should be open when the pedal is moved and closed when stopped, but maybe its the opposite. Does the ohm change when the pedal is moved? Since debris was around the machine when it developed the issue, maybe something ripped a wire? Take a look at the schematic and confirm if all the safeties are in parallel or series, also the normal operation of the switches....

 

[Billdog350]

Unless the circuitry is looking for a resistor, usually you can jumper out switches for troubleshooting