Testing Fuel Shut off solenoid

Rook

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Equipment
BX-23
Feb 24, 2018
6
0
0
Clinton, CT 06413
BX-23 (vintage 2005) will not shut off. Fuse is OK. What is procedure for testing shutoff solenoid? What about a faulty key switch - how can I test that? Is there a simple way to jump the key switch?
 

William1

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BX25D
Jul 28, 2015
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Richmond, Virginia
Running tractor, unplug the solenoid. The tractor should stop. If it does not, rust or a faulty return spring.
If the solenoid was staying energized, your battery would discharge pretty quickly unless you keep the tractor on a maintainer.
 
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07wingnut

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Feb 13, 2016
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As I recall, the fuel shutoff solenoid on the BX23 is normally in the fuel on position with no power applied to it. When shutting down, the timer applies 12 volts to the solenoid for a short period of time to shut down the tractor. When you turn the tractor off with the key, you should hear the fuel solenoid kick in, to shut down the fuel flow and the engine , and then a few seconds later, kick back out to allow fuel flow for the next start up.
Put a voltmeter on the solenoid wire and see if this voltage shows up when you turn off the key. If not, you may have a timer problem, ignition switch problem, or the wiring in between.
 

Rook

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Equipment
BX-23
Feb 24, 2018
6
0
0
Clinton, CT 06413
Good info from both of you. Got more questions...just got the machine 2 weeks ago. Changing all fluids and filters. Spec’s say engine crankcase with filter 2.6 qts. Did that and barely at low level mark on dip stick. At 3 qts, dip stick reads almost 1/2 way between low mark and high mark. What is recommended fill level? Similar situation in change transmission/hydraulic fluid - spec’s call out 2.7 gallons with filter change. Barely reaching the bottom of the dip stick. Have not driven the tractor or operated any implements as of yet.
Just not sure if I should continue filling until I am close to high level marks on dipsticks, or go by capacities called off in spec’s???
 

North Idaho Wolfman

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Good info from both of you. Got more questions...just got the machine 2 weeks ago. Changing all fluids and filters. Spec’s say engine crankcase with filter 2.6 qts. Did that and barely at low level mark on dip stick. At 3 qts, dip stick reads almost 1/2 way between low mark and high mark. What is recommended fill level? Similar situation in change transmission/hydraulic fluid - spec’s call out 2.7 gallons with filter change. Barely reaching the bottom of the dip stick. Have not driven the tractor or operated any implements as of yet.
Just not sure if I should continue filling until I am close to high level marks on dipsticks, or go by capacities called off in spec’s???
Fill it to the high mark on both.
 

Rook

New member

Equipment
BX-23
Feb 24, 2018
6
0
0
Clinton, CT 06413
As I recall, the fuel shutoff solenoid on the BX23 is normally in the fuel on position with no power applied to it. When shutting down, the timer applies 12 volts to the solenoid for a short period of time to shut down the tractor. When you turn the tractor off with the key, you should hear the fuel solenoid kick in, to shut down the fuel flow and the engine , and then a few seconds later, kick back out to allow fuel flow for the next start up.
Put a voltmeter on the solenoid wire and see if this voltage shows up when you turn off the key. If not, you may have a timer problem, ignition switch problem, or the wiring in between.
Disconnected the solenoid pigtail from wiring harness. Jumped the solenoid at quick with directly from spare 12V quad battery. Solenoid actuated and shut engine off...great. Turned key on and checked to see if getting juice to solenoid quick disconnect on wiring harness side of plug,,,yes, 12V. Tested ignition switch resistance per WSM instructions - thought I found the problem. Bought new ignition switch - still does not shut down engine. Thinking it might have something to do with timer you mentioned. Timer is shown in wiring diagram, but there does not seem to be any mention of it anywhere elsein WSM. Do you know where the timer is located?? And what it looks like??
 
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North Idaho Wolfman

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The timer is under the dash.



Put a test light on the side that feeds the stop solenoid, with the key off you should get nothing, key on you should get nothing turn the key off the wire should be powered for about 5 seconds.
On this system there are normally 2 Fuses that run it one one the input to the timer and one on the Hot lead that the timer sends to the stop solenoid.
 

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Rook

New member

Equipment
BX-23
Feb 24, 2018
6
0
0
Clinton, CT 06413
Thanks NIW. More helpful info from the fine state of Idaho! Was looking under dash today, saw a couple modules (items 200 and 330 in you parts diagram) suspected one of them to be timer. You attachment clarifies that! Will test as you suggested, but probably won’t be able to get back on this problem for a while. I am fearing there may be a wiring harness short.
 

Rook

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Equipment
BX-23
Feb 24, 2018
6
0
0
Clinton, CT 06413
I am stymied with regard to why my BX-23 (vintage 2005) will not shut off with the ignition switch. I have replaced the ignition switch and the solenoid timer module. The solenoid appears to work when I hotwire it directly to a battery, it activates and shuts the motor off.
Does anybody have suggestions to offer???
 

100 td

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B21TLB (B21, TL421 & BT751) Toyota SDK4 T116 Bobcat
Aug 29, 2015
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ɹǝpunuʍop
Do you have a WSM/circuit diagram? If so post it up. You may also have a key stop relay in circuit which the timer switches to power the shut off solenoid. Solenoid main fuse should be 15~30 amps I expect, and a 5~10 amp on the control circuit.
 

Rook

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Equipment
BX-23
Feb 24, 2018
6
0
0
Clinton, CT 06413
Hey Journeyman;
Wiring diagram in WMS indicates 15 amp breaker in line t0 timer. I am not clear if that is in addition to the fuse in the fuse box?? I have yet to locate any in-line fuses?? Any ideas where I might look? Wiring diagram also seems to indicate a relationship to the HST foot pedal neutral switch, the PTO switch, and the seat support switch in the circuit to timer and solenoid??? Can use all the help I can get!
 

Justin Charles

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Equipment
2008 Kubota MX5000SU
Feb 22, 2021
9
0
1
Ocala, Florida
The timer is under the dash.



Put a test light on the side that feeds the stop solenoid, with the key off you should get nothing, key on you should get nothing turn the key off the wire should be powered for about 5 seconds.
On this system there are normally 2 Fuses that run it one one the input to the timer and one on the Hot lead that the timer sends to the stop solenoid.
I have an MX500SU Kobota that keeps blowing a 10A fuse when I try to start the engine. If I remove the fuel solenoid it will start and not blow the fuse. I’ve replaced the solenoid with no change. From your post it sounds like the timer or the relay could be the culprit. I traced the wires and can’t find any issue with something going to ground. Any thoughts will be greatly appreciated!! Thanks - Justin Charles
 

Henro

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I have an MX500SU Kobota that keeps blowing a 10A fuse when I try to start the engine. If I remove the fuel solenoid it will start and not blow the fuse. I’ve replaced the solenoid with no change. From your post it sounds like the timer or the relay could be the culprit. I traced the wires and can’t find any issue with something going to ground. Any thoughts will be greatly appreciated!! Thanks - Justin Charles
There is currently an almost identical thread going on here. Maybe a different tractor model. You might look for that thread and see if it is of any help. Sorry, I can not remember the thread title or easily supply a link to it, or I would.
 

Shad9147

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Equipment
3600
Jan 15, 2023
8
0
1
Ohio
As I recall, the fuel shutoff solenoid on the BX23 is normally in the fuel on position with no power applied to it. When shutting down, the timer applies 12 volts to the solenoid for a short period of time to shut down the tractor. When you turn the tractor off with the key, you should hear the fuel solenoid kick in, to shut down the fuel flow and the engine , and then a few seconds later, kick back out to allow fuel flow for the next start up.
Put a voltmeter on the solenoid wire and see if this voltage shows up when you turn off the key. If not, you may have a timer problem, ignition switch problem, or the wiring in between.
Should this timer still activte power just turning key on&off without starting?
 

Shad9147

New member

Equipment
3600
Jan 15, 2023
8
0
1
Ohio
The timer is under the dash.



Put a test light on the side that feeds the stop solenoid, with the key off you should get nothing, key on you should get nothing turn the key off the wire should be powered for about 5 seconds.
On this system there are normally 2 Fuses that run it one one the input to the timer and one on the Hot lead that the timer sends to the stop solenoid.
Thanks.this test should work even without actually starting tractor correct?got a l 3600 with no power to fuel selonoid.
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
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Sandpoint, ID
Yes the timer just cycles with key on and off, powers the Solenoid for about 5 seconds.

And yes a bad timer can pop that fuse.
 

Shad9147

New member

Equipment
3600
Jan 15, 2023
8
0
1
Ohio
So with no power at selonoid I'll check the timer&fuses.what triggers the timer when key is turned off? power from key switch?
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
30,599
6,629
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Sandpoint, ID
So with no power at selonoid I'll check the timer&fuses.what triggers the timer when key is turned off? power from key switch?
Key on sets it up
Key off triggers the ~5 seconds of power to the solenoid.