Re: Kubota L48 starting problems

[MONTY747]

Re: Kubota L48 starting problems

I have a Kubota L48TLB with starting problems. will crank over, all lights on dash seem ok, no smoke from exhaust. I replaced the stop solenoid, didn't fix the problem, I can loosen the stop solenoid so its plunger or rod is released from the injector block, tractor will start. I can then shut it off by just pushing in the stop solenoid to where its supposed to be bolted. Seems like the stop solenoid is not getting juice to it to make it operate. Would it be the starter relay? As I stated, with the stop solenoid in place, everything seems to work properly, glow plugs, etc, but could crank engine forever and it won't start. Release the stop solenoid, starts right up. Help! Thanks for any input, I'm pretty poor at using voltmeters, etc. and Kubota wiring diagrams suck. Some time back, the glow plug light kept coming on when running and I replaced the glow plug relay and the controller. That fixed that problem.

 

[ns_in_tex]

Re: Kubota L48 starting problems

On my Kubota L4610, the engine quits as soon as I cut the key off. I am presuming, by shutting the fuel off. Maybe 30 seconds later, I hear a click. I think this may be the fuel shut off solenoid turning the fuel back on, making it ready for the next start. Not sure how all this works, but if I am right, maybe it will give you something to think about until someone who knows, gives you a more complete answer.

 

[Industrial Toys]

Re: Kubota L48 starting problems

SOME fuel solenoids (on Kubotas) have two circuits, pull in and hold. I think the pull in is related to a starter circuit. I guess on that type, you would not hear the solenoid when turning on the key. Only when the starter is energized. I have scratched my head on these two step solenoids. ESPECIALLY when they are tied into safety switches!

 

[MONTY747]

Re: Kubota L48 starting problems

Thanks. I believe it has something to do with stop solenoid circuit. It's been raining here, so haven't been out working on this, but got suggestions from two different Kubota dealers. Both said check out stop solenoid circuit for power, one suggested timer relay, other suggested timer relay or key switch as the problem. I'll check these out soon.

 

[MONTY747]

Re: Kubota L48 starting problems

Well, that was a waste of $28.00. Was suggested relay switch behind the dash could be the problem. Kubota dealer said they sell a lot of the relays, so I gave it a try. No luck. Starts on first revolution when stop solenoid is disengaged, but just cranks if it's engaged. Will try testing with voltmeter next, if I can get someone to show me how to do it. wiring diagram looks like current goes into both leads on stop solenoid.

 

[cycle_gator]

Re: Kubota L48 starting problems

Perhaps check where the solenoid grounds. See other current thread “Strange Fuel Solenoid Problem” Looks very similar.

 

[MONTY747]

Re: Kubota L48 starting problems

Well, found the problem! It was a relay under the dash. I had changed out stop solenoid, and other relays, didn't fix. I couldn't determine from the Kubota manual, what part number this relay was, so I took it to the local Napa Auto Parts store. They found, in their book, the matching relay, Napa part # AR565. Had to order it, getting delivered the next morning. Put it in, tractor is back to normal! Thanks for the different inputs. Case Closed!

 

[radios1]

Re: Kubota L48 starting problems

Well, found the problem! It was a relay under the dash. I had changed out stop solenoid, and other relays, didn't fix. I couldn't determine from the Kubota manual, what part number this relay was, so I took it to the local Napa Auto Parts store. They found, in their book, the matching relay, Napa part # AR565. Had to order it, getting delivered the next morning. Put it in, tractor is back to normal! Thanks for the different inputs. Case Closed!

the failure may have been caused by moisture, like when people store their tractors outside, and expect no issues with that..

 

[fried1765]

Re: Kubota L48 starting problems

the failure may have been caused by moisture, like when people store their tractors outside, and expect no issues with that..

I keep everything inside!
Tractors/trailers/cars/trucks/boats/mowers/implements/etc.
My mother taught me to put my toys away each night.... 78 years ago.