I have a Kubota M8560 cab tractor that has been nothing short of a major headache if the temperature is under 10°. Since it was brand new we've had issues where it either runs very poorly or not at all. The local dealer has sold us endless fuel filters and sediment bowl filters as well as a sediment bowl heater. They've gone as far as having us cut the diesel fuel with 5 gallons of kerosene. Still nothing has seemed to fix it. This is the 3rd midsize Kubota we've purchased new and with this much of a headache and disappointment it will likely be the last. We have paid thousands of dollars to the local dealer and they always seem to think it's fixed until the next cold snap. Bottom line, if it's under 10° outside you might as well forget using it and use the M6040 instead. Any advice or thoughts would be greatly appreciated. Thanks.
M8560 cold weather issues
- Thread starter Snow2dirt
- Start date
Dealer with diagmaster can find the problem, quickly, efficiently. Fixing it may be another issue in itself, but just ask them to diagnose and nothing more. That is the only foolproof way to know, just like the new diesel trucks. The days of us working on stuff out at the farm are about over unless it's an older tractor.
I would think it's a glow plug issue, which is controlled by engine coolant temperature. So it's possible that there could be an issue with the glow system (relay, wiring, etc) or a problem with the temperature sensing system (sensor, wiring, etc). Or potentially an ECU problem but that'd be rare.
I would think it's a glow plug issue, which is controlled by engine coolant temperature. So it's possible that there could be an issue with the glow system (relay, wiring, etc) or a problem with the temperature sensing system (sensor, wiring, etc). Or potentially an ECU problem but that'd be rare.
I have to say I'm impressed with our Kubota tractors performance through this last cold snap! We have only had one service call to a common rail engine and that was because it couldn't quite reach enough coolant temp to start a regen sitting outside at 30 below! ( a little cardboard in front of the rad helped it out)
All the rest of them have started up,done their job, and no complaints! And thats a lot of tractors
Thanks for the input, it seems as tho the service department at the local dealer knows as much about the tractor as the neighbors dog. I have a 2015 Gmc Denali with all the emissions b.s. on it and haven't had a single issue. I think kubota knows the M8560 and M9960 were a problem but don't want to stand behind it and thats why they already moved on from those particular models. It's extremely frustrating to have spent 58k on a cab tractor that is only good for summer use. It doesn't throw any lights or flash any type of code. I can continue sending it to the local dealer but I'd be better off waiting for warm weather or just using my tier 3 M6040 which is 10x the tractor that M8560 will ever be. EXTREMELY frustrated with the tractor and lack of a decent service department.
It is a shame that your dealer is stymied. Can you get, as lugbolt suggests, their records of the previous diagmaster tests? (assuming they were smart enough to write them down, or maybe they are even on your bill since it sounds like they charged you).You might then be able to go to Kubota and get some communication with the regional service rep who should be more knowlegeable. Much of this part of the system should still be under warranty. It is ridiculous your tractor only works in the summer. Start with the Kubota online email help line, but be prepared to persevere.
Snow2dirt
Welcome to OTT
My guess is your tractor has fuel delivery problem. Have you or dealer installed fuel conditioner? Normally once engine has started operating then glow-plugs are no longer utilized. I once owned a M4900 that gave me problems loosing power & local Kubota service manager told me about a small screen in fuel shut off valve(key 020). I checked screen to determine it was clogged,cleaned screen then engine ran great. I have no idea if this applies to your tractor but it would be easy to check.
Welcome to OTT
My guess is your tractor has fuel delivery problem. Have you or dealer installed fuel conditioner? Normally once engine has started operating then glow-plugs are no longer utilized. I once owned a M4900 that gave me problems loosing power & local Kubota service manager told me about a small screen in fuel shut off valve(key 020). I checked screen to determine it was clogged,cleaned screen then engine ran great. I have no idea if this applies to your tractor but it would be easy to check.
Attachments
All these fixes seemed to be focused on elements that are downstream of the fuel tank.
If there is a problem with production debris in the tank that it could be the tank strainer that's is partially clogged and has ice accreted on it.
If you have condensate in the tank, it can freeze on the strainer. Kerosene will help a wax problem but it won't deal with a water issue. Since it's a cold weather issue, do you see signs of water in the fuel during the summer months? Do your filters have drains on them? Do you drain them regularly into a clear container and look for signs of water in the fuel?
Do you have a lift pump? Does it have a screen that you can clean off?
Just some things to think about for a vexing problem like this.
I had a similar issue and found that my fuel/water separator bowl wasn't sealing well in the housing. I pulled the fuel line from the outlet of the lift pump and put an extra piece of line on it routed to a bucket. The fuel flow was sputtering and irregular. As I played with the bowl, the flow varied and I finally got it into the magic spot and flow cleaned up to a steady stream. Hooked the line back up and the tractor started right up.
Every few days it rattles loose and I have to play with it again to get it going.
Problem is much worse when it is cold out. I have a new bowl and O-rings on the way.
Any air leak between the tank and the the lift pump could cause a lot of issues. The suction from the lift pump can probably seal minor leaks if the parts are flexible, but when cold most things aren't very flexible.
Every few days it rattles loose and I have to play with it again to get it going.
Problem is much worse when it is cold out. I have a new bowl and O-rings on the way.
Any air leak between the tank and the the lift pump could cause a lot of issues. The suction from the lift pump can probably seal minor leaks if the parts are flexible, but when cold most things aren't very flexible.
Do you know of the glow plug controller bypass technique.
It has been a big help to many M series owners.
I will send you a pm with the details
I think hooking up a temporary fuel supply to the injection pump from a very clean container like for an outboard motor with a prime bulb. Have the tank higher than the injection pump so gravity and siphoning will supply the injection pump.
That way you are by passing many fuel supply things and if your tractor improves you have narrowed down the problem.
Dave