Starts easily but won't stay running

[StandSureForge]

I have a 2001 Kubota M9000. For the last few months I have found it starts immediately but once I release the key it dies. This happens ususlly 2 or 3 times prior to it continuing to run. Lately it is taking 5 or 6 attempts to make it stay running. Any advice?

 

[Edke6bnl]

I had a bad ignition switch that would start my b7800 tractor and instead of going to run it went to off when i let go of the key. New switch in my case worked

 

[Russell King]

I have a 2001 Kubota M9000. For the last few months I have found it starts immediately but once I release the key it dies. This happens ususlly 2 or 3 times prior to it continuing to run. Lately it is taking 5 or 6 attempts to make it stay running. Any advice?

There is probably a solenoid that allows the tractor to be turned off with the key (and engine stops running). The same solenoid is probably used to stop the engine if one of the safety switches is not set properly.

That solenoid should get power in the run position and the crank position of the key switch.

If your tractor is reliable when it is running (doesn’t just die for unknown reason), then it sounds like there is some problem in the key switch that sometimes is not providing power in the run position.

There may be something more complicated if the tractor has a lot more sophistication with a lot of electronics like an ECU that is monitoring the tractor’s operation.

 

[StandSureForge]

I had a bad ignition switch that would start my b7800 tractor and instead of going to run it went to off when i let go of the key. New switch in my case worked

Thank you, I hadn't considered that.

 

[StandSureForge]

There is probably a solenoid that allows the tractor to be turned off with the key (and engine stops running). The same solenoid is probably used to stop the engine if one of the safety switches is not set properly.

That solenoid should get power in the run position and the crank position of the key switch.

If your tractor is reliable when it is running (doesn’t just die for unknown reason), then it sounds like there is some problem in the key switch that sometimes is not providing power in the run position.

There may be something more complicated if the tractor has a lot more sophistication with a lot of electronics like an ECU that is monitoring the tractor’s operation.

I'll look at the key switch, was leaning that way too. Yes, once it starts it runs great. Appreciate the help.

 

[007kubotaguy]

Most likely the key switch

 

[3Owls]

Most likely the key switch

Thank you was having the same issue. Thought a good way to test was heat the switch. Took my heat gun and heated switch to 100 degrees, fire up the tractor and it kept running. Woohoo. I was sure it was fuel related. In checking that I pulled the plug on the injection pump port, and looked inside. The cavity was empty, is that normal? I haven't been able to find any info on the injection pump. Tractor is a 2004 L5030.

 

[GreensvilleJay]

are you 100% sure the glow plugs are 100% working ?
20 year old engine, stuff doesn't last forever
Maybe 1 or two are weak ?
I know my 6 year old BX23S ALWAYS starts if I give it 5 seconds of preheat. When I don't, it stalls then takes longer to run properly.
Another possibility would be the 'lift' pump . if it's weak,not enough fuel get to the injectors until engine is running smooth ?

 

[3Owls]

are you 100% sure the glow plugs are 100% working ?
20 year old engine, stuff doesn't last forever
Maybe 1 or two are weak ?
I know my 6 year old BX23S ALWAYS starts if I give it 5 seconds of preheat. When I don't, it stalls then takes longer to run properly.
Another possibility would be the 'lift' pump . if it's weak,not enough fuel get to the injectors until engine is running smooth ?

Not sure who you are replying to.

 

[GreensvilleJay]

The original poster.......
BTW if you have a different model even with similar problem , you should post your own post as not all Kubota engines are the same for all models,so what fixes one may not fix others.

 

[North Idaho Wolfman]

are you 100% sure the glow plugs are 100% working ?
20 year old engine, stuff doesn't last forever
Maybe 1 or two are weak ?
I know my 6 year old BX23S ALWAYS starts if I give it 5 seconds of preheat. When I don't, it stalls then takes longer to run properly.
Another possibility would be the 'lift' pump . if it's weak,not enough fuel get to the injectors until engine is running smooth ?

Why would the glow plugs stop the engine from running?

 

[North Idaho Wolfman]

Thank you was having the same issue. Thought a good way to test was heat the switch. Took my heat gun and heated switch to 100 degrees, fire up the tractor and it kept running. Woohoo. I was sure it was fuel related. In checking that I pulled the plug on the injection pump port, and looked inside. The cavity was empty, is that normal? I haven't been able to find any info on the injection pump. Tractor is a 2004 L5030.

I don't know what port your talking about?

 

[BAP]

The original poster.......
BTW if you have a different model even with similar problem , you should post your own post as not all Kubota engines are the same for all models,so what fixes one may not fix others.

So you are telling others not to answer a post giving their experiences with a different model but you do it all the time in many different threads. Are you special?

 

[GreensvilleJay]

why, cause they don't get the engine hot enough to self ignite the fuel before key is put to 'run'.
similar to taking choke of an old gas engine, it usually dies

 

[3Owls]

I don't know what port your talking about?

As your looking at the injection pump, just below bleeder valve there is a 1"+/- rubber stopper. You can pull it and look into the injection pump.

 

[North Idaho Wolfman]

As your looking at the injection pump, just below bleeder valve there is a 1"+/- rubber stopper. You can pull it and look into the injection pump. View attachment 144365

AWWWW that is an oil fill port, Kubota engines have several of them.

Ands no you won't see anything in there except residual oil.

 

[North Idaho Wolfman]

why, cause they don't get the engine hot enough to self ignite the fuel before key is put to 'run'.
similar to taking choke of an old gas engine, it usually dies

They don't work like that.

 

[3Owls]

AWWWW that is an oil fill port, Kubota engines have several of them.

Ands no you won't see anything in there except residual oil.

Wow, been doing my own maintenance for 10 years, and never knew. Majorly easier than through the valve cover. Thank you!