BX2200 not running with key in run

[Henro]

also interesting the starters are different which may explain why yours wont crank with out the solenoid attached. By the wiring diagram it should as I described earlier.

As I tried to convey above, on the solenoid with only two wires leading to the two internal coils, while the schematic diagram shows a third wire going to the chassis ground from the solenoid, the reality is there is no third wire, and the path to ground is through the solenoid body, which is bolted to the injector pump, which is at chassis ground.

The starter solenoid circuit, continues through the starter and on through the start coil of the fuel cutoff solenoid. then to ground through the physical connection to the injector pump. This is reason the starter will not turn when the fuel cutoff solenoid is hanging in the air. No path for electrical current to return to the battery.

Again, I am only speaking about my vintage BX2200. Some produced during the end of the run before the next model may have the wiring of the next model. This seems to be something somewhat commonly done by Kubota.

 

[Fordtech86]

Id be curious to see the diagram for your version. And also running two solenoids in series in this case wouldnt work.

Ill PM you if you would like me to illustrate how it works.

 

[Henro]

Id be curious to see the diagram for your version. And also running two solenoids in series in this case wouldnt work.

Ill PM you if you would like me to illustrate how it works.

You already posted the diagram. But it is a schematic diagram/wiring diagram combo. So it cannot be taken as an actual wiring diagram. But it is electrically accurate as shown, as even without the third wire the functionality is the same, because the grounding of the solenoid body acts the same as a third wire would.

The fuel cutoff solenoid on my BX2200 is a single armature, dual coil solenoid. The start coil has much lower resistance than the hold(run) coil. I measured it but do not remember the values.

I know how the circuit works. No need for an explanation here. Once it is understood that the start coil is energized by the current passing through the starter solenoid it is easy to see. That detail is not readily apparent on the Kubota schematic.

Actually, it would likely be helpful if you would explain how you think the circuit works, for future readers of this thread. If you explanation is different than my experience I will add what I know.

What I think we do know is that the OP has a three wire solenoid and my BX has a two wire solenoid. If this is the case, why would that be? Obviously it would have to be because the wiring between our two BX2200 tractors is different. And why would they be different? Possibly because a change was made during the transition to the next model. Speculation on my part.

If I were energetic I would find a schematic for the BX2230 and see what the differences between the two models are. But I am not going there as I have other things that are more pressing requiring my time.

 

[Fordtech86]

You already posted the diagram. But it is a schematic diagram/wiring diagram combo. So it cannot be taken as an actual wiring diagram. But it is electrically accurate as shown, as even without the third wire the functionality is the same, because the grounding of the solenoid body acts the same as a third wire would.

The fuel cutoff solenoid on my BX2200 is a single armature, dual coil solenoid. The start coil has much lower resistance than the hold(run) coil. I measured it but do not remember the values.

I know how the circuit works. No need for an explanation here. Once it is understood that the start coil is energized by the current passing through the starter solenoid it is easy to see. That detail is not readily apparent on the Kubota schematic.

Actually, it would likely be helpful if you would explain how you think the circuit works, for future readers of this thread. If you explanation is different than my experience I will add what I know.

What I think we do know is that the OP has a three wire solenoid and my BX has a two wire solenoid. If this is the case, why would that be? Obviously it would have to be because the wiring between our two BX2200 tractors is different. And why would they be different? Possibly because a change was made during the transition to the next model. Speculation on my part.

If I were energetic I would find a schematic for the BX2230 and see what the differences between the two models are. But I am not going there as I have other things that are more pressing requiring my time.

You don’t understand how it works. Give me some time

 

[Henro]

You don’t understand how it works. Give me some time

Get real!

I own one and had the exact same problem with a failed fuel cut off solenoid. I know EXACTLY how the system on my BX2200 works. Without question.

I would also tell you that I spent several decades as an engineer in heavy industry trouble shooting and improving complex control systems. So this simple circuit is simply...simple. I am only reacting to your accusation that I do not understand the circuit. Normally I would not mention my past life experience in this regard.

Take all the time you want, but please post something that will help others in the future. AND do not tell people what they do not know, when you do not know them or their background.

Edit: You may have sucked my in to making this response, but hey, that's life I suppose...

 

[Fordtech86]

Get real!

I own one and had the exact same problem with a failed fuel cut off solenoid. I know EXACTLY how the system on my BX2200 works. Without question.

I would also tell you that I spent several decades as an engineer in heavy industry trouble shooting and improving complex control systems. So this simple circuit is simply...simple. I am only reacting to your accusation that I do not understand the circuit. Normally I would not mention my past life experience in this regard.

Take all the time you want, but please post something that will help others in the future. AND do not tell people what they do not know, when you do not know them or their background.

Edit: You may have sucked my in to making this response, but hey, that's life I suppose...

Let me make sure what you are claiming…you are saying the starter solenoid is grounded through the stop solenoid?

 

[Henro]

Let me make sure what you are claiming…you are saying the starter solenoid is grounded through the stop solenoid?

What I was trying to express, is that the starter solenoid is activated by a circuit that has several safety switches in it. I forget which ones. One is the gear range selector which needs to be in neutral.

The interesting thing is that the current path that flows through the starter solenoid continues through the starter, and is connected to the start coil of the fuel cutoff solenoid. In the case of my BX2200, the start coil, as well as the hold, or run, coil, is grounded through the solenoid body, via the contact with the injector pump it is bolted to. It is this current that activates the starter solenoid, that also causes the start coil of the fuel cutoff solenoid to pull the armature in.

The Hold coil, or call it the run coil, is energized, but not strong enough to pull the fuel cut off solenoid armature in, but is strong enough to hold it in once the start coil pulls it in.

The unexpected part of this is, when looking at the Kubota schematic, that it is not apparent that the current that activate the starter solenoid, has to flow through the start coil of the fuel cutoff solenoid, before the starter will be activated.

AND with my BX2200, with a two wire fuel cut off solenoid, the solenoid must be connect to chassis ground before current will flow through the starter solenoid.

Please take the time to understand what I am trying to convey. I realize that written communication is sometime difficult.

At the end of the day, the whole purpose of this conversation and thread is to help the OP and anyone else that may read the thread later...

 

[Fordtech86]

What I was trying to express, is that the starter solenoid is activated by a circuit that has several safety switches in it. I forget which ones. One is the gear range selector which needs to be in neutral.

The interesting thing is that the current path that flows through the starter solenoid continues through the starter, and is connected to the start coil of the fuel cutoff solenoid. In the case of my BX2200, the start coil, as well as the hold, or run, coil, is grounded through the solenoid body, via the contact with the injector pump it is bolted to. It is this current that activates the starter solenoid, that also causes the start coil of the fuel cutoff solenoid to pull the armature in.

The Hold coil, or call it the run coil, is energized, but not strong enough to pull the fuel cut off solenoid armature in, but is strong enough to hold it in once the start coil pulls it in.

The unexpected part of this is, when looking at the Kubota schematic, that it is not apparent that the current that activate the starter solenoid, has to flow through the start coil of the fuel cutoff solenoid, before the starter will be activated.

AND with my BX2200, with a two wire fuel cut off solenoid, the solenoid must be connect to chassis ground before current will flow through the starter solenoid.

Please take the time to understand what I am trying to convey. I realize that written communication is sometime difficult.

At the end of the day, the whole purpose of this conversation and thread is to help the OP and anyone else that may read the thread later...

I understand exactly what you are trying to say. Ill be back

 

[Fordtech86]

The starter solenoid circuit, continues through the starter and on through the start coil of the fuel cutoff solenoid. then to ground through the physical connection to the injector pump. This is reason the starter will not turn when the fuel cutoff solenoid is hanging in the air. No path for electrical current to return to the battery.

Bear with me, this isn’t easy on a phone.

Here is power flow when you turn the key to start.

I bypassed the safety switches for simplicity.

from the battery, through the slow blow fuse, to the ignition switch. From there it goes through the safeties to the starter relay. The starter solenoid is energized and grounded through the starter case (circled in blue)

That pulls the plunger over to make the contact for the pull solenoid circuit

the starter solenoid engagement has to happen first to make the contact. The pull coil circuit for the stop solenoid does get power from the starter solenoid circuit, but its tied in parallel.

So now you have to visualize because the diagram shows it at rest. The starter solenoid energizes and pull the plunger over to make the contact. Power is then applied to the pull coil circuit.

It is its own circuit in parallel with the starter solenoid but they share the same feed.

What I understand you are saying is they are wired in series. That would never work in this scenario.

Im going to make this simple with round numbers. If these were two identical solenoids wired in series, each solenoid would get 6 volts. You only have 12 volts available for all loads to share in series. Say the starter solenoid uses 10 of those volts to activate, that only leaves 2 volts to activate the stop solenoid. It wont work.

Will add more to this….

This connection from the starter solenoid to the pull circuit is used to direct the flyback voltage when the starter solenoid disengages. This will maintain the hold circuit during the ignition switch transition from start to run.

 

[Fordtech86]

The starter solenoid has to work independently of the stop solenoid to make it work

 

[Henro]

Bear with me, this isn’t easy on a phone.

Here is power flow when you turn the key to start.




View attachment 68240

View attachment 68260
This connection from the starter solenoid to the pull circuit is used to direct the flyback voltage when the starter solenoid disengages. This will maintain the hold circuit during the ignition switch transition from start to run.

First it should be said that Kubota schematic drawings are not always accurate and often confusing. So unless you actually have had a BX2200 starter apart and traced the wiring and internal component connections, you are making a huge assumption that what is shown, internally to the starter, is actually the way things are.

Further, believing the inductive kick of the solenoid produces enough energy to hold the low resistance start coil in, is unrealistic. But even if it could for a short time, the starter would be disengaged at that moment, the engine would stop turning, and the fuel would not be delivered in time for the engine to start.

On top of that, if the system actually did work like you think, why would the starter motor NOT turn when the fuel cut off solenoid is unplugged, or left plugged in but physically removed from the engine? This is NOT speculation, but a fact with my BX2200.

The moment the starter starts to turn, the run coil pulls the fuel cutoff solenoid armature in, and the hold coil, that is already energized, holds the armature in the run position. From that point forward the run coil is out of the picture as far as normal operation goes.

There is no timer relay on the BX2200. It is used on the BX1800. Another example of Kubota drawing confusion if one does not realize this.

I think your posts have a lot of correct detail, and will be helpful so someone in the future. But you seem to dispute what is indeed fact with respect to MY BX2200.

I do not doubt that the OP's BX2200 acts differently. And that his has a 3 wire connector while mine has 2 wires. AND the only reason I can imagine it is so, is because it possibly could share the wiring setup of the following model. Or maybe there was a change made in the middle of the production run. I do not know what the actual reason might be.

I hope what has turned into a debate is helpful to someone in the future...

 

[Fordtech86]

Ok, yeah Ill back up a little on the flyback voltage holding the stop solenoid for a brief second, its just using that circuit to dissapate that voltage after the starter solenoid releases.

why would the starter motor NOT turn when the fuel cut off solenoid is unplugged, or left plugged in but physically removed from the engine?

So here the pull coil circuit needs a 12 volt source separate from the starter solenoid circuit too have them on two parallel circuits. When you physically remove the stop solenoid in your case it takes the two solenoids and now puts them in series where they are now sharing a ground through the starter case and they are both fighting for the voltage and neither can activate.

 

[Henro]

Ok, yeah Ill back up a little on the flyback voltage holding the stop solenoid for a brief second, its just using that circuit to dissapate that voltage after the starter solenoid releases.


So here the pull coil circuit needs a 12 volt source separate from the starter solenoid circuit too have them on two parallel circuits. When you physically remove the stop solenoid in your case it takes the two solenoids and now puts them in series where they are now sharing a ground through the starter case and they are both fighting for the voltage and neither can activate.

If the wiring is similar to what is shown in the Kubota drawing, the inductive kick of the starter solenoid coil would certainly be dissipated through the start coil of the solenoid like you mention.

Actually the pull in coil voltage required is unknown, because on my BX2200 the start coil is in series with the starter solenoid apparently, so in theory it would feel less than 12 volts. It is the current that passes through the solenoid coil, that produces the magnetic flux to cause the armature to move to the run position, against force of the spring that causes the armature to return to the off position (when voltage is removed from the hold coil, when the key is turned to the off position). I believe the workshop manual test procedure uses 12 volts on each of the fuel cutoff solenoid coils for test purposes, so they are rated at 12 volts.

When the solenoid (in my case) is removed from the injector pump, the two coils do become essentially connected in series, because the mid point ground connection is removed, but since both are activated by the same 12 volt battery, they will either feel 12 volts on each end of the hookup, or one, or both ends will have no voltage (open circuit), so they will not pass current and therefore become meaningless in that situation. This is because the ground return path for current has been removed. I believe I am just saying what you stated in a different way, but do not see any fight going on between the solenoid coils...

I hope the OP reports back with his final solution.

 

[Fordtech86]

I hope the OP reports back with his final solution

yep, me too.

Actually Henro, you brought up something I had forgotten about, so for that I do want to pass along a sincere thank you.

 

[Henro]

yep, me too.

Actually Henro, you brought up something I had forgotten about, so for that I do want to pass along a sincere thank you.

Nothing beats discussing things, especially if they might help someone who is in need of advice. I think our discussion was worthwhile, and that the specifics you posted should help someone in the future, if not the current poster.

 

[dover7838]

Sorry for the delay. Weather been trash in central Indiana and work been demanding.

based upon recommendation here, tested voltage between terminals on this attached diagram.

Im getting 12-14 v at the stop solenoid. When I turn key to stop, getting 0 as should be expected.

 

[Henro]

Sorry for the delay. Weather been trash in central Indiana and work been demanding.

based upon recommendation here, tested voltage between terminals on this attached diagram.

Im getting 12-14 v at the stop solenoid. When I turn key to stop, getting 0 as should be expected.

Been a while, but the blue wire in your drawing should have 12 volts on it when the key is in the start position and the starter is turning.

The green wire should have voltage on it whenever the key is in the on or start position.

IF you are not getting 12 volts on the blue wire, when the key is in the start position the tractor should turn the engine over but not run when the key is in the start position. But you say the engine starts but does not continuing running when the key is released from the start position. So the start circuit part of the circuit seems to be working.

It sounds like you are also saying that the voltage on the green wire is 12 volts when the key is on, and goes to 0 volts only when the key is turned to the off position. This is as expected.

So it appears that your solenoid is not working correctly. You can remove it from the injector pump, and start the engine, and watch the solenoid armature. The armature (plunger, whatever you want to call it) should retract when you start the tractor and stay retracted after the key is released from the start position.

If you do this you will have to replace the solenoid by hand to shut the engine off. Just holding it in place should do the job. OR you can test the solenoid following the procedure outlined in the WSM.

It certainly sounds like the solenoid armature is not being held in when the key is in the run position. If I understand what you said in the last post, my bet is the solenoid is defective, or you have a bad connection at the terminal where you are measuring voltage.

Edit: One caveat I think has been mentioned previously in this thread. Your BX2200, if one of the last BX2200s produced, could share the control wiring of the next model in the series. If so, it may have wiring different from that shown in the drawing you posted. Your drawing matches my BX2200 perfectly.

 

[dover7838]

Been a while, but the blue wire in your drawing should have 12 volts on it when the key is in the start position and the starter is turning.

The green wire should have voltage on it whenever the key is in the on or start position.

IF you are not getting 12 volts on the blue wire, when the key is in the start position the tractor should turn the engine over but not run when the key is in the start position. But you say the engine starts but does not continuing running when the key is released from the start position. So the start circuit part of the circuit seems to be working.

It sounds like you are also saying that the voltage on the green wire is 12 volts when the key is on, and goes to 0 volts only when the key is turned to the off position. This is as expected.

So it appears that your solenoid is not working correctly. You can remove it from the injector pump, and start the engine, and watch the solenoid armature. The armature (plunger, whatever you want to call it) should retract when you start the tractor and stay retracted after the key is released from the start position.

If you do this you will have to replace the solenoid by hand to shut the engine off. Just holding it in place should do the job. OR you can test the solenoid following the procedure outlined in the WSM.

It certainly sounds like the solenoid armature is not being held in when the key is in the run position. If I understand what you said in the last post, my bet is the solenoid is defective, or you have a bad connection at the terminal where you are measuring voltage.

Edit: One caveat I think has been mentioned previously in this thread. Your BX2200, if one of the last BX2200s produced, could share the control wiring of the next model in the series. If so, it may have wiring different from that shown in the drawing you posted. Your drawing matches my BX2200 perfectly.

working on this issue now. Using voltmeter was getting 12volts on the “hold side” continuously. Was getting 12 volts when key turned to retract the piston. On a whim, put old stop solenoid back on. It worked fine. Tractor starts and stops with the key. So, it Appears replacement stop solenoid is defective.

however, still do not have turn signals or hazard lights. I have headlights and tail lights. My ROPS auxiliary lights work too.

At this point, I’m running replacement key/starter assembly, and original stop solenoid. Tractor starting and stopping as it should.

I believe I replaced stop solenoid first, before key assembly. So when I did that, with defective solenoid, I thought it was the key causing the problem. So replaced that too. Might have been defective key assembly from the get go?

I still have an issue between key, and the hazard/turn signal lights.

 

[Henro]

working on this issue now. Using voltmeter was getting 12volts on the “hold side” continuously. Was getting 12 volts when key turned to retract the piston. On a whim, put old stop solenoid back on. It worked fine. Tractor starts and stops with the key. So, it Appears replacement stop solenoid is defective.

however, still do not have turn signals or hazard lights. I have headlights and tail lights. My ROPS auxiliary lights work too.

At this point, I’m running replacement key/starter assembly, and original stop solenoid. Tractor starting and stopping as it should.

I believe I replaced stop solenoid first, before key assembly. So when I did that, with defective solenoid, I thought it was the key causing the problem. So replaced that too. Might have been defective key assembly from the get go?

I still have an issue between key, and the hazard/turn signal lights.

I know it’s been a while, but I just stumbled on this thread again, and realized that on my BX2200 I have the same issue with my hazard/turn signals not working.

Forgot about it as I rarely have the need for them.

Hopefully the OP will stop back and report how he resolved the problem with the flashers.

 

[DustyRusty]

I know it’s been a while, but I just stumbled on this thread again, and realized that on my BX2200 I have the same issue with my hazard/turn signals not working.

Forgot about it as I rarely have the need for them.

Hopefully the OP will stop back and report how he resolved the problem with the flashers.

Not until he has another problem with his tractor.......... joined Oct 16, 2021 Last seen Dec 7, 2021