MX 5800 Starting Issue

[bdhsfz6]

On several occasions, I have been unable to restart the MX immediately after shutting it down. I wait for the glow plug light to go out but get nothing when turning the key. I get no click of the starter solenoid, just the clicking sound of the fuel pump. Waiting for some unknown period of time seems to solve the issue. Twice now, I've been forced to abandon the tractor in the field only to return some time later and have it start right up.

This is new to me and has never occurred on any of my previous four B and L series tractors. To further complicate things, the problem is intermittent and does not occur every time. Warm or cold, it seems to make no difference. I always shut the tractor down for safety when getting off to check an implement. Now I'm afraid to do it fearing it won't start again. I'm familiar with the starter interlocks for clutch, PTO, seat etc. Is there a new one to consider? The manual makes no mention of these symptoms. Anyone else experience this?

 

[motownbrowne]

There's also the safety switch on the treadle for the HST. I've had that one be a little touchy before. Beyond going through the checklist of switches when it happens, it sounds like the next step involves a multimeter to track down the problem. Good luck!

 

[FatTire]

There's also the safety switch on the treadle for the HST. I've had that one be a little touchy before. Beyond going through the checklist of switches when it happens, it sounds like the next step involves a multimeter to track down the problem. Good luck!

I'll second this one. The symptom sounds just like a treadle pedal that's not returning exactly to neutral. I've had it happen but only in cold weather, just jiggle the pedal a little to get it back to the true "middle".

 

[Luke'sScreenName]

I'll second this one. The symptom sounds just like a treadle pedal that's not returning exactly to neutral. I've had it happen but only in cold weather, just jiggle the pedal a little to get it back to the true "middle".

If you'd like, I can take a pic of the electrical quick connect that by disconnecting you disable both the seat and treadle safety switches. No jumpers required. Might help for a rule-out.

 

[FatTire]

If you'd like, I can take a pic of the electrical quick connect that by disconnecting you disable both the seat and treadle safety switches. No jumpers required. Might help for a rule-out.

Wow, are you saying there is one thing to disconnect that disables both of these safety switches??!!

 

[bdhsfz6]

Thanks for the advice. I'm familiar with the treadle interlock. When the problem occurs, moving it makes no difference. I had a treadle interlock switch fail on my old L3010 HST, maybe that's the problem here as well. The MX5800 is the first regen tractor I've owned. I thought there might be another interlock there.

Anyway, thanks for the help.

 

[Luke'sScreenName]

Wow, are you saying there is one thing to disconnect that disables both of these safety switches??!!

Correct.

 

[FatTire]

Correct.

Please do post some info. Never knew about this.

 

[Luke'sScreenName]

Following the seat switch wires to JUST below the floor board. There is a QD there. Pull it apart. :drink:

 

[FatTire]

Following the seat switch wires to JUST below the floor board. There is a QD there. Pull it apart. :drink:

Thanks, will try it.

 

[rScotty]

On several occasions, I have been unable to restart the MX immediately after shutting it down. I wait for the glow plug light to go out but get nothing when turning the key. I get no click of the starter solenoid, just the clicking sound of the fuel pump. Waiting for some unknown period of time seems to solve the issue. Twice now, I've been forced to abandon the tractor in the field only to return some time later and have it start right up.

This is new to me and has never occurred on any of my previous four B and L series tractors. To further complicate things, the problem is intermittent and does not occur every time. Warm or cold, it seems to make no difference. I always shut the tractor down for safety when getting off to check an implement. Now I'm afraid to do it fearing it won't start again. I'm familiar with the starter interlocks for clutch, PTO, seat etc. Is there a new one to consider? The manual makes no mention of these symptoms. Anyone else experience this?

Intermittant starting is sure a rotten problem! By which I mean...How are you to know if you've fixed it? Is it when it stops letting you walk home alone? Sure would be nice to find a part to replace.
It does sound like one of the safety switches, and luckily you have the knowledge to find it eventually. Frankly I'd do about what you are doing and expect about the same results.

Something to consider is that back before machines had so many safety interlock switches this would probably turn out to be poor or worn contacts inside the starter solenoid. And when it didn't start the problem would have been diagnosed by using a HEAVY wire to jump either across the large terminals of the solenoid or directly from battery to starter. FWIW, I'd add a few jumper cables of various sizes and connectors to the tractor's tool box along with a volt/ohm meter. Then when it gets stubborn the nex time you stand a chance of isolating the offending part.

The only thing I don't like about my advice is that it doesn't take into account the fact that the tractor has probably cooled down when you come back and it starts right up. What could that be? Is that a clue to something else? Should we be looking there instead of intermittant electrics? That bothers me... But basically I agree with all the others. The "no click of the solenoid" seems to point at safety interlocks.

BTW, there's also an interlock on the clutch pedal of my similar sized tractor. Yes, weirdly enough the Kubota M59 has a clutch pedal even though it is a HST. I'm guessing it is about the same motor as the M5800.
luck,
rScotty

 

[bdhsfz6]

The MX5800 starting issue turned out to be a flaky seat interlock switch. That also explains an intermittent problem I had when mowing last summer. The engine would cut out when mowing a slope or when I would turn around in the seat to mow in reverse.

I bypassed the seat switch temporarily until my next trip to the dealer. The tractor is still under warranty but I will probably have to take the machine in to get it replaced. The dealer used to just give me a simple part and let me replace it myself. Those days seem to be over. Rather than go through the hassle of getting the machine over there, I may just leave the bypass in place. If the tractor needs to go in for a more serious problem, I'll let them replace the switch then.

In any case, thanks everyone for your help.

 

[motownbrowne]

The MX5800 starting issue turned out to be a flaky seat interlock switch. That also explains an intermittent problem I had when mowing last summer. The engine would cut out when mowing a slope or when I would turn around in the seat to mow in reverse.

I bypassed the seat switch temporarily until my next trip to the dealer. The tractor is still under warranty but I will probably have to take the machine in to get it replaced. The dealer used to just give me a simple part and let me replace it myself. Those days seem to be over. Rather than go through the hassle of getting the machine over there, I may just leave the bypass in place. If the tractor needs to go in for a more serious problem, I'll let them replace the switch then.

In any case, thanks everyone for your help.

Glad you got it figured out. I certainly understand keeping that switch intact, but for my use, it's not feasible to leave it there. I'm constantly standing up to see the tips of my forks or check how close I am to something I'm working next to. I think I zip tied that switch on about day three of owning my MX. But, I don't have young people using my machine, and I try to thoroughly train any new operators and make them aware that driving the tractor is an inherently dangerous thing to do.

 

[bdhsfz6]

Glad you got it figured out. I certainly understand keeping that switch intact, but for my use, it's not feasible to leave it there. I'm constantly standing up to see the tips of my forks or check how close I am to something I'm working next to. I think I zip tied that switch on about day three of owning my MX. But, I don't have young people using my machine, and I try to thoroughly train any new operators and make them aware that driving the tractor is an inherently dangerous thing to do.

I see your point. I just picked up a QA pallet fork and I have to agree, having the engine quit every time you stand up is a major PIA. I suspect the longer I go with that bypass in place, the less likely I'll be to remove it.

 

[Luke'sScreenName]

I see your point. I just picked up a QA pallet fork and I have to agree, having the engine quit every time you stand up is a major PIA. I suspect the longer I go with that bypass in place, the less likely I'll be to remove it.

I made the same choice.