BX25 will not turn off

[Robs2544]

Good evening,

Had a little issue with my machine after plowing an hour ago, went to turn the key off, tractor kept on running. Lights also stayed on, factory lights and the LED light bar I installed. I ended up pulling the ACC 20 amp fuse and it killed the lights and engine.

Any ideas on what the issue could be?

Thanks in advance!
Rob

 

[Tomtint]

My fathers BX 23 was doing that a few years ago.there is a manual fuel shut off on the ( I think ) right side of the motor as you sit on it. It's a small lever looking thing that starves the motor of fuel until it stalls. I honestly don't remember what the problem that caused it was... may have been a bad ignition if I recall correctly.

 

[David_Kb7uns]

I am thinking that since the lights stayed on, I would be looking at the key switch being faulty. If you turned the key off and the lights and other accessories turned off but the key timer relay did not energize the stop solenoid killing the engine I would look at the key stop timer circuit or a bad fuse.

There is an exposed solenoid usually on engine by injection pump that will energize and pull the stop lever to stop the engine, this is energized by a timed relay that is activated when the key is turned off or one of the seat or interlock switches are tripped. sometimes one of the fuses blows and keeps the system from working properly.

David

 

[DMW]

Check fusebox first (on the left side below the light switch). One of them will control the fuel shutoff solenoid. It may be burnt out.

Dennis

 

[Volfandt]

Sounds like it's blown the 20amp fuse. That circuit is for the safety switches and electric shutdown. The wires that many use for ROPS lights are also in that circuit. As been stated, theres a manual cutoff lever on the fuel injector pump, be very careful reaching down to move it as it's close enough to the fan to warrant caution. The lever is spring loaded and only moves in one direction. If it weren't for all those safety switches a knob and cable connected to that lever would be all one would need to shut down a diesel. Thats how old diesels were shut down.
I'm not sue where the 20amp fuse is located on a BX25 but on my BX23 it's in the wiring near the starter. Check that area as well as under the dash. It's usually a stand alone type fuse that just hangs from the wiring, it's very obvious.
Good luck
Dave

 

[Robs2544]

Just to clarify, when I switch the key off the motor, dash lights, ROPS LED light and headlights all stay on. I'm thinking it's the ignition switch as well. I pulled the 20amp ACC fuse which is located in the fuse box on the right side of the machine under the ignition switch. There are 6 total fuse in this box, the 20amp one if in the bottom left corner. Once that fuse is removed everything turns off. When I reinstall the fuse, with the keys out, everything turns on beside the motor.

Thanks to all that replied!

 

[Robs2544]

Update on this issue. I changed the ignition, no good, the tractor still stays running, dash and lights still function with the key off and removed. I pulled the 20amp fuse, everything shut off. So, I put the key back in and turned the tractor on, dash and lights work and the tractor fires up with the 20amp fuse removed! So there must be an issue with that 20 amp circuit? The fuse is not blown, I tried 2 different 20 amp fuses.

I also did a trial and error with a few more fuses. If I pull the "timer" fuse it kills the motor (ignition off, not key) but the dash still functions.

I'm pretty sure the fuel cut-off is on the left side for the BX25 (sitting on tractor). That lever is moving when I start the tractor and turn off.

Pretty lost, not a fan of working with electrical issues at all.

 

[Peter 315]

Is there a relay stuck on the 20 amp circuit ?

 

[anthonyv]

Don't know if this will help but my WSM for BX24, which should be close has these options to check.

 

[anthonyv]

After rereading the first post if you pulled the 20amp fuse & killed everything, something is wrong in the fuse panel or wiring around it. My schematic shows that fuse only controls the red/black wire in the rear of the tractor for working or aux lights & normally is not connected to anything unless you have installed lights. There should be a black gnd wire along with this one taped or stored somewhere around the tail lights. Shutoff solenoid, fuel pump, & timer are controlled by the 15amp fuses.

 

[Volfandt]

I'm linking to an old thread where we stepped through a similar problem on a BX23. The BX25 "may" still retain the same method of operation.
Good luck
http://www.tractorbynet.com/forums/...x23-solenoid-location.html?highlight=volfandt



From post #7:
All-righty then, armed with my trusty multimeter and a hard copy of the WSM schematic, I've got some readings and I believe an idea (dangerous, I know ) on how the D905 stop solenoid and assoiciated safety switch operations work on my BX23.

The solenoid itself is normally in the "run" position and is temporarily electrically energized to "off" (to cut off fuel flow in the injector pump).
You can physically disconnect the solenoid and the engine will start & run but of course you'll have to manually use the shutdown lever to shut it off. And you'll also not have any safety shutdown features either. It does not use a "holding" voltage or coil for it's run operation. It must rely on spring tension alone to return the solenoid's plunger to the normal (run) position.

There are two wires feeding to the stop solenoid, a white and a black. The black is tied to permanent ground and the white is connected to the Timer Relay which is located under the dash.
The timer relay controls the voltage to the stop solenoid. The timer relay has two different input voltage circuits that control it. One input circuit has a 15amp fuse and is always hot.
The other input circuit has the 20amp fuse and feeds through both seat switches and the pto switch, the HST pedal switch and is turned on/off via the key switch.

The reason for two inputs to the timer relay is two fold. The always hot input is the actual working voltage that is passed on to the stop solenoid.
The other input that goes through all the safety switches is used to actuate the timer relay and also to power the delay timer circuitry. This is the "control" circuit.

When all the safety switches are in the correct positions (made or shorted contacts) and the key turned on, power is applied to the timer relay though the control circuit. There is NO 12v applied to the stop solenoid. The engine is started and the stop solenoid stays in its unpowered unenergized state.
If one raises up from the seat and with the pto engaged (except in the rear only position) and/or depresses the HST pedal voltage is removed from the timer relay "control circuit" which inturn causes it to immediately apply 12v to the stop solenoid for approx 10 sec's, then the timer relay clicks off and voltage is once again removed from the stop solenoid. 10 seconds is plenty enough time to shut down the D905.

When the key is turned Off it basically removes 12v from the timer relay in the same manner as a safety switch "tripping" which causes the timer relay to apply approx 10 sec's of 12v to the stop solenoid.

Well thats my theory of operation so lets get to some troubleshooting tips.
1) unplug the stop solenoid and using a multimeter or even a 12v lamp, plug one lead into the black recepticle and the other lead to the white recepticle.
Turn the key switch on, you should NOT read any voltage. If you do the timer relay is bad. (note, I've not read of one of these ever going bad yet but anything can fail).

2) Now turn the key switch off. You SHOULD read 12v for approx 10 sec's then it should go away. You will also hear the timer relay click under the dash. (it is not as loud as the stop solenoid click but you can hear it click).
If you do get this reading then your stop solenoid is bad.

3)If you do not get 10 sec's of 12v then the timer relay is bad OR one of the safety switches are not "making" OR(and more likely) the 20amp fuse is blown. The 15amp fuse could also be blown but the 20amp fuse is the main culprit as it also feeds the aux "hot" connector located under the seat that alot of folks like to use to power ROPS lights etc.

Good luck and let us know what you find.

 

[David_Kb7uns]

The D905 had the internal solenoid with the run and hold winding, the newer BX has the D902 "Super Mini Series" engine where there is an external solenoid that is just energized to pull the stop lever.

The Dx02 and Dx05 or Dxx05 engines use different systems, my RTV1100 with the D1105 and my L3130 with the D1503 both shut down when battery power to solenoid is lost.

David

 

[Volfandt]

So your saying the 902's have an external solenoid that pulls the stop lever on the fuel injection pump? Interesting.
A pic would be nice. That solenoid could be the OP's problem. Does it hold the lever in the stop location for a similar duration as the D905 i.e. 10-15 secs., then release it back?
The shutoff system on my 04 BX23 w/the D905 has worked as designed without problem, must have been a change in the fuel injection pump that necessitated how the electric shutdown was redesigned.for the D902 series.

 

[David_Kb7uns]

The D905 solenoid has ears where it bolts to the engine and the plunger pushes against the arm inside the injection pump holding against a spring that would push the arm into the stop position. When power is cut to the solenoid the spring pushes the lever and the engine stops.

The D902 solenoid is mounted adjacent to the speed control lever and pulls the lever into the stop position when energized. The safety switch circuit takes power from the key switch and there are a few parallel loops within the circuit that will bypass the PTO lever if the seat is raised forward, but any break in the circuit makes remove power to the Keystop TImer Relay making it activate for the required time to energize the stop solenoid and stay energized long enough for the engine to come to a complete stop (this is the circuit with the 5amp fuse that people find blown).


David


D905 solenoid on left D902 solenoid on right