BX23 solenoid location

   / BX23 solenoid location #1  
R

Rusty4242

Bronze Member
Joined
Mar 24, 2007
Messages
97
Location
Western Mass.
Tractor
Kubota BX23
Since my BX23 still won't shut down with the key( I attached a cord to the fuel cut off lever) I need to test the cut off solenoid, but can't find it. By the way, when I turn the key to the off position, the revs seem to go up very slightly.( the fuses are all ok, though the seat cut off switch isn't working)

\Any help would be appreciated. Thanks, Larry
 
   / BX23 solenoid location #2  
The solenoid is located on the fuel injector pump. There have been a few posts where this has gone bad on BX23's/BX2230's and there is a test proceedure in the WSM to determine whether its bad or not.
When you checked the fuses did you check the 20 amp fuse out of circuit with a continuity tester? They can look good but still be blown.
Good luck.
http://www.mytractorforum.com/attachment.php?attachmentid=14417&d=1159033952
 

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   / BX23 solenoid location
  • Thread Starter
#3  
Trouble is that my solenoid is different from the one in your picture and what's in my WSM. Mine is a Denso unit , about about 2 1/2 " long and 1 1/2 " in dia with only 2 leads, a black and a red. When powered up the plunger pops out until power is removed. It is on the same wires that feed the head light on that side. So I guess it works, but not as described in the WSM. By the way, the solenoid fuse test OK. Any other ideas? Larry
 
   / BX23 solenoid location
  • Thread Starter
#4  
OK, I just found other posts on the problem. I'll check out the wiring connectors.
Hopefully, Larry
 
   / BX23 solenoid location #5  
Just checked out the wiring on my 04 BX23 and it's not like the WSM either. I've got the D905 engine and it has only two wires to the stop solenoid connector, white and black. On the stop solenoid side of the connector they change to red and black.
I printed off the wireing schematic and will study it some when I get alittle extra time this evening. A quick glance seems to show either some misprints and/or incomplete details.
Some of these model will run without the solenoid installed, I'm now curious if thats the case with ours.
We'll cypher it out :D
 
   / BX23 solenoid location #6  
Try using a meter on the wires going into the solenoid. Some of the solenoids have a third wire for ground and some are grounded through the frame connection. Most of the solenoids that I have seen that mount in the pump body like on the D905 have a run coil and a shut off coil. One winding will have a higher resistance than the other. The D902 that I have on the BX2230 has an external solenoid that pulls the lever closed and only has one coil. Somewhere in the production of the BX23 they changed the engine layout and wiring.

David Kb7uns
 
   / BX23 solenoid location #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 :D) 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.
 
   / BX23 solenoid location
  • Thread Starter
#8  
Here's what I have today. I took the sol. out and bench tested it with 2 amps of a 12 volt battery charger. It poped out just fine. I put it back in and put a meter on it's supply lead( just after the headl light) and got 12 volts. I got that voltage with the engine running with the key in the run position, and with the key in the off position. The current was there even 10 min. after I shut it down with the cut off lever. When I put the key in the extreme off position, the engine sounds as if the rpms have changed a little. ALso, in the off position, the meter on the sol. feed line drops about a volt. Another note, when I hook the wires back up to the sol. after determineing that they are hot, I don't get any sound of sol. activation at all. Thoughts? Thanks to all of you for scratching you collective head over this. Larry
 
   / BX23 solenoid location #9  
Thats definitely different from the readings I got on a known working BX23. There shouldn't be 12v sitting on the stop solenoids white lead.
Matter of fact, it's surprising that the engine starts at all considering that theres 12v on it at all times.
I guess it's possible Kubota changed the design of the stop solenoid assembly on the BX23 w/the D905 engine in mid production but lets try a few static tests.

Question 1, your's only has two wires to it, right?
Question 2, when you bench tested the solenoid, did the rod return very forcefully when you removed power to it?
I ask because my solenoid makes a very loud and distinct "clunk" when the rod returns after the power is removed.

1)With the elec connector disconnected from the stop solenoid, turn the key on. The only sound you should hear is the elec fuel pump clicking.
After 5-10 secs or so turn the key off. Now listen carefully, you should hear the timer relay click off within 10 to 15 secs after you turned the key off. It's not a very loud click but I could easily hear mine.

On my BX23, the 12v supplied to the stop solenoid comes through the timer relay and and it's only there for approx 12 sec's after the key switch is turned off, unless there was a production change, yours should too.

The timer relay is up under the dash. The WSM doesn't give any troubleshooting or test proceedures for it unfortunately and if you don't hear it click when you do the test above, then I'd suspect that the timer relay's contacts could be "welded" in the "make" position. That could explain the constant voltage to the stop relay. You could remove it and tap it to see if this free's them up.

Good luck
 
   / BX23 solenoid location #10  
Semi-sorta related question:

So the solenoid opening back up is the click I hear a few seconds after shut-down? :confused:
 
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