BX1860 will not start

hudson68

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BX1860;LA203-Loader;RCK54-29B MP Mower;Land Pride RB1560 Rear Blade
Sep 10, 2019
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Winchester, CT
I have a Kubota BX1860 that will not start nor is there any signs of combustion.

I have performed the following to the fuel system:
  • Removed fuel tank and cleaned out the garbage left by the decaying fuel level unit. (A considerable amount of rust was present). Reinstalled tank
  • Replaced all fuel supply lines from fuel tank to fuel injector pump
  • Replaced (2) inline fuel filters
  • Replaced electric fuel lift pump
  • Fresh diesel fuel
  • Bled air at injector pump body inlet
  • Bled air at injector nozzle inlets, one at a time
The starter turns over the engine normally but there are no indications of combustion.
The glow plug indicator light illuminates.
There is no sign of fuel oil or coolant in the motor oil.

The engine stop solenoid is pulling in and out but I’m a little unclear to it’s sequence of operation. This machine incorporates a Operator Presence Control amid a Timer Relay.

One of my first questions is: What is the normal lever position on fuel the valve connected to the solenoid? Power to the solenoid retracts the plunger, does this cut fuel or open?

Second question: What am I missing?
Prior operation was standard except for having to occasionally blow fuel line back into tank to clear. The machine was shut down normally without any indication of malfunction. I have worked 1800 hours on this machine and maintained as required. Other than a tremendous amount of broken plastic body pieces, there are no abnormal disturbing signs of wear, leaks, or smoke.

Any and all advice is welcomed and greatly appreciate.
 

85Hokie

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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
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When you bled - did fuel spit out from the bleed nut or injector?

What happened to make IT STOP running?

IS the air filter clean and nothing stopping air flow?
 

hudson68

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BX1860;LA203-Loader;RCK54-29B MP Mower;Land Pride RB1560 Rear Blade
Sep 10, 2019
13
0
1
Winchester, CT
When you bled - did fuel spit out from the bleed nut or injector?

What happened to make IT STOP running?

IS the air filter clean and nothing stopping air flow?
I bled it at the bleed nut with sufficient flow and each injector inlet nut individually.

Nothing happened other than turning the key to off which is why I’m so perplexed.

No air flow restrictions.
 

85Hokie

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Did you even get ANY type of smoke at all?
 

Dieseldonato

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Very odd that if you have fuel up to the injectors with the lines cracked it didn't attempt to fire off. Also unlikely that you got that much trash into the injector pump or injectors that they would all fail at once. I would suspect there's air trapped somewhere in the fuel system yet. Particularly at the injectors. They can be quite bother some to bleed sometimes. They should kinda spirt at you once the air is bleed out. Normally even if only 1 or 2 fire off it will clear itself out in short order.
 

hudson68

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BX1860;LA203-Loader;RCK54-29B MP Mower;Land Pride RB1560 Rear Blade
Sep 10, 2019
13
0
1
Winchester, CT
Very odd that if you have fuel up to the injectors with the lines cracked it didn't attempt to fire off. Also unlikely that you got that much trash into the injector pump or injectors that they would all fail at once. I would suspect there's air trapped somewhere in the fuel system yet. Particularly at the injectors. They can be quite bother some to bleed sometimes. They should kinda spirt at you once the air is bleed out. Normally even if only 1 or 2 fire off it will clear itself out in short order.
Is it apparent to bleed at each injector inlet nut individually or can/should be performed on all 3 concurrently? I loosen the inlet flare nut enough to separate the pipe from the seat. I’m turning the engine over until I see fuel “dribbling “ out of the top of nut. I haven’t disconnected the pipe from injector completely. Is this sufficient?
The shut off valve that is controlled by the solenoid is spring assisted. What position is the valve in its normal position without connected to solenoid, open or closed? Knowing this gives me an idea if the relay timer is malfunctioning and what I would need to do to temporarily bypass. The WS manuals I have are unclear. In addition all Kubota literature I have state that the fuel system is bled by the lift pump via the return lines. I can hear the fuel returning to the tank when key is on. Unless something abnormal is happening when start circuit is energized, I’m quite confused.
Thank you
 

Dieseldonato

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Should be more of a spirt from out behind the nut of the injector. The solenoid is spring loaded to shut off fuel. It pulls the plunger in to allow fuel to flow in the injection pump.
 

Henro

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B2910, BX2200, KX41-2V mini Ex.
May 24, 2019
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Is it apparent to bleed at each injector inlet nut individually or can/should be performed on all 3 concurrently? I loosen the inlet flare nut enough to separate the pipe from the seat. I’m turning the engine over until I see fuel “dribbling “ out of the top of nut. I haven’t disconnected the pipe from injector completely. Is this sufficient?
The shut off valve that is controlled by the solenoid is spring assisted. What position is the valve in its normal position without connected to solenoid, open or closed? Knowing this gives me an idea if the relay timer is malfunctioning and what I would need to do to temporarily bypass. The WS manuals I have are unclear. In addition all Kubota literature I have state that the fuel system is bled by the lift pump via the return lines. I can hear the fuel returning to the tank when key is on. Unless something abnormal is happening when start circuit is energized, I’m quite confused.
Thank you
At this point I would remove the fuel cut off solenoid and see if the engine starts and runs. If you do this you will have to manually put the solenoid back in place to shut the engine down, if it does starts. I am assuming your BX is similar to my BX2200/1800 series.

BX tractors for the most part (maybe all) self bleed using the lift pump and do not require manual bleeding, at least when things work correctly.

If you remove the solenoid you will at least get some focus on which direction to go next. If the engine starts, likely an electrical control issue. If the engine still doesn’t start likely a fuel supply issue. Divide and conquer …
 

hudson68

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BX1860;LA203-Loader;RCK54-29B MP Mower;Land Pride RB1560 Rear Blade
Sep 10, 2019
13
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Winchester, CT
Should be more of a spirt from out behind the nut of the injector. The solenoid is spring loaded to shut off fuel. It pulls the plunger in to allow fuel to flow in the injection pump.
Your explanation of solenoid operation tells me a great deal. Mine seems to be working opposite. Even activation of the PTO safety retracts the plunger. I’m going to remove solenoid and position valve to replicate “safe”. Thank you for explaining.
 

Henro

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B2910, BX2200, KX41-2V mini Ex.
May 24, 2019
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Your explanation of solenoid operation tells me a great deal. Mine seems to be working opposite. Even activation of the PTO safety retracts the plunger. I’m going to remove solenoid and position valve to replicate “safe”. Thank you for explaining.
I think there may be some misunderstanding of what "in" means.

"In" as stated by DieselT means, at least in the case of my BX, that the plunger is pulled INTO the solenoid, and out of the injector pump, in order for the engine to run. I would bet the BX1860 works the same way. But I always lose if I bet...

The spring in the solenoid "pushes" the plunger out of the solenoid housing, and into the injector pump, in my case, when power is removed. BUT it could be set up to work the other way too by a manufacturer.

In the case of my solenoid, there is no way to see what the plunger (actually called the armature) is doing, without taking the solenoid off the injector pump. So if you are able to see what is going on with the solenoid mounted, yours must be different.
 

DustyRusty

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BX23S
Nov 8, 2015
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If it were running prior to your "repair", then it should run again, assuming that you reassembled everything correctly. If you didn't mess with the fuel solenoid valve, then it should still be working correctly after changing fuel lines and filters. I had a similar problem with my BX22 when it stopped running suddenly. I replace the filters and bled it as you did, and then it wouldn't start. I also put a new pump in, which turned out the be the original problem. I turned the key on and walked away for 15 minutes while the pump kept pumping fuel to the injectors and back to the tank. When I came back, I used the glow plugs for about 30 seconds and then turned the key to start. It started but ran rough for a few minutes, until it cleared itself, and no more problems.
 
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Dieseldonato

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They can be bears to get the air worked out if the fuel system.
 

whitetiger

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The fuel shutoff solenoid is mounted above the injection pump, and the injection pump is spring-loaded to the RUN position. To shut off the engine, the current is applied to the solenoid which then retracts for 7 to 10 seconds. The current will then be stopped by the timer and the solenoid will extend and return the injection pump to the RUN position.
 

Dieseldonato

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The fuel shutoff solenoid is mounted above the injection pump, and the injection pump is spring-loaded to the RUN position. To shut off the engine, the current is applied to the solenoid which then retracts for 7 to 10 seconds. The current will then be stopped by the timer and the solenoid will extend and return the injection pump to the RUN position.
Interesting, the few smaller kubota tractors I've worked on had them all behind the injection pump. Good to know there's 2 different styles.
 

hudson68

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Equipment
BX1860;LA203-Loader;RCK54-29B MP Mower;Land Pride RB1560 Rear Blade
Sep 10, 2019
13
0
1
Winchester, CT
The fuel shutoff solenoid is mounted above the injection pump, and the injection pump is spring-loaded to the RUN position. To shut off the engine, the current is applied to the solenoid which then retracts for 7 to 10 seconds. The current will then be stopped by the timer and the solenoid will extend and return the injection pump to the RUN position.
This is the correct operation of my machine. There must be opposite set ups out there. Thank you.
 

RCW

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BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
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The bleeding procedure of my BX2360 is to run the electric lift pump for 20(?) seconds, then start as usual.

My shut off solenoid works as yours; returns to RUN position 5-7 seconds after shut down.
 

hudson68

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BX1860;LA203-Loader;RCK54-29B MP Mower;Land Pride RB1560 Rear Blade
Sep 10, 2019
13
0
1
Winchester, CT
If it were running prior to your "repair", then it should run again, assuming that you reassembled everything correctly. If you didn't mess with the fuel solenoid valve, then it should still be working correctly after changing fuel lines and filters. I had a similar problem with my BX22 when it stopped running suddenly. I replace the filters and bled it as you did, and then it wouldn't start. I also put a new pump in, which turned out the be the original problem. I turned the key on and walked away for 15 minutes while the pump kept pumping fuel to the injectors and back to the tank. When I came back, I used the glow plugs for about 30 seconds and then turned the key to start. It started but ran rough for a few minutes, until it cleared itself, and no more problems.
I’ve attempted every fix except letting the lift pump run for an extended period of time. I will try this and let everyone know the outcome. Everyone’s time and advice is appreciated.
 

hudson68

New member

Equipment
BX1860;LA203-Loader;RCK54-29B MP Mower;Land Pride RB1560 Rear Blade
Sep 10, 2019
13
0
1
Winchester, CT
They can be bears to get the air worked out if the fuel system.
I discovered that the solenoid operation on my particular machine is opposite from yours. However I would have never known this without disconnecting the solenoid and propping the lever valve against its normal spring assist position. By doing this and cracking the injector nut I wasn’t getting fuel at that point any longer. Putting the lever valve back to it’s resting position allowed the “dribbling “ to continue. With this said, I’m back to troubleshooting. I agree that the fuel system is air bound. Thank you