m4050 Random Starts

Airgator

New member

Equipment
Kubota M4050
Jan 22, 2022
22
0
1
Florida
I have had problems getting my m4050 started. The battery was checked and it was fine.
I replaced the starter because it was making a whirring or grinding sound.
Once I replaced the starter and the battery was charged the tractor started at the first turn of the ignition
the first few times. Now when I am trying to start the tractor and I turn the ignition switch I may turn the switch
5 or 6 times with no sound and then it will make some noise and start. Sometimes I have to turn the switch again to heat the glow plugs and it takes more than 5 or 6 turns. It may take a few times of heating the plugs and trying. Why is it so random that I can turn the ignition switch and get no noise and then it will just start? I have been checking the battery so the battery is good. The battery terminals and cables are clean. What could it be that it isn't totally dead and keeps starting eventually? (I hope this continues, by the way). As you can tell, I have very little experience with tractors. I appreciate any thoughts. Is there some other part that may be the problem?
 

JerryMT

Active member

Equipment
Kubota M4500, NH TD95D,Ford 4610
Jun 17, 2017
434
96
28
The Palouse - North Idaho
I have had problems getting my m4050 started. The battery was checked and it was fine.
I replaced the starter because it was making a whirring or grinding sound.
Once I replaced the starter and the battery was charged the tractor started at the first turn of the ignition
the first few times. Now when I am trying to start the tractor and I turn the ignition switch I may turn the switch
5 or 6 times with no sound and then it will make some noise and start. Sometimes I have to turn the switch again to heat the glow plugs and it takes more than 5 or 6 turns. It may take a few times of heating the plugs and trying. Why is it so random that I can turn the ignition switch and get no noise and then it will just start? I have been checking the battery so the battery is good. The battery terminals and cables are clean. What could it be that it isn't totally dead and keeps starting eventually? (I hope this continues, by the way). As you can tell, I have very little experience with tractors. I appreciate any thoughts. Is there some other part that may be the problem?
Check the ground cable where it attaches to the tractor. Make sure it is "tight and bright". Make sure the wiring to the starter solenoid i isn't loose at the starter. It could also be a bad starter switch.
 

Russell King

Well-known member

Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
3,207
424
83
Austin, Texas
You need to determine if there is any voltage on the smaller wire on the starter solenoid.

The starting circuit generally is from battery to key switch through safety switches to the wire on the solenoid. If voltage is applied to the solenoid it throws the bending gear out and applies voltage to the starter motor.

I assume something is breaking the circuit and no voltage is being applied to that wire. You can test it with a voltage meter or a test light to see if that is what is happening when trying to start the tractor.

I have assumed that your tractor is simple and not loaded with computer controls but I imagine that the same problem would occur at the starter, just troubleshooting the cause will be more difficult if there are more computers involved.
 

Airgator

New member

Equipment
Kubota M4050
Jan 22, 2022
22
0
1
Florida
Check the ground cable where it attaches to the tractor. Make sure it is "tight and bright". Make sure the wiring to the starter solenoid i isn't loose at the starter. It could also be a bad starter switch.

Just to be sure I'm doing the right thing....you mean where the negative cable attaches to the tractor?
It looks like it could use a cleaning. Thank you.
 

Airgator

New member

Equipment
Kubota M4050
Jan 22, 2022
22
0
1
Florida
You need to determine if there is any voltage on the smaller wire on the starter solenoid.

The starting circuit generally is from battery to key switch through safety switches to the wire on the solenoid. If voltage is applied to the solenoid it throws the bending gear out and applies voltage to the starter motor.

I assume something is breaking the circuit and no voltage is being applied to that wire. You can test it with a voltage meter or a test light to see if that is what is happening when trying to start the tractor.

I have assumed that your tractor is simple and not loaded with computer controls but I imagine that the same problem would occur at the starter, just troubleshooting the cause will be more difficult if there are more computers involved.
Yes, it is from 1982 to 1985 so it doesn't have a lot of bells and whistles or electronics. I will see what I can do with a meter. Thank you.
 

Russell King

Well-known member

Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
3,207
424
83
Austin, Texas
If you only have the clutch safety switch that may be your problem? You may want to see if it is activated (with a meter) every time you push the clutch pedal down, clean the wire connections or bypass it when it is not cranking to see if it will crank.
 

GreensvilleJay

Well-known member

Equipment
BX23-S
Apr 2, 2019
4,982
1,664
113
Greensville,Ontario,Canada
re: Yes, it is from 1982 to 1985

So when, if ever, was the ignition switch replaced ? Interrmitant, random starting could very easily be the ignition switch(have to assume,it's been used a zillion times in 37 years )
 

Airgator

New member

Equipment
Kubota M4050
Jan 22, 2022
22
0
1
Florida
re: Yes, it is from 1982 to 1985

So when, if ever, was the ignition switch replaced ? Interrmitant, random starting could very easily be the ignition switch(have to assume,it's been used a zillion times in 37 years )
I have owned the tractor for less than a year. It’s hard to know if it’s original or not…but I get your point.