My B7800 kubota tractor having issues with the fuel solinode. Tractor dies all of a sudden and will not start. It cranks but will not start due to fuel solinode not receiving 12v. I've tried resetting by letting it sit for a few minutes with no results. I return to it several hours latter and its if nothing wrong with it. Starts with no problem. Sometimes it runs all day with no issue. I definitly know that the fuel solinode does not receive 12v during down time. Any ideas?
No volts to fuel solinode
- Thread starter I-R-S
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The following thread may offer some insight although the issue was a little different. The tractor is the same and the issue he was having related to the fuel solenoid...
B7800 no start issue
This is my first post, and have read a bazillion threads regarding any issues I've had with my B7800. First I want to thank everyone for taking the time to respond to all the questions that seem simple but not so simple to solve. I've been searching the forum about everything concerning the...
www.orangetractortalks.com
Did you even bother putting a multi-meter on the solenoid plug to see or are you relying on sound?
rbargeron
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When I first got my B7800 and before I had the chance to check everything out I had a similar problem that you describe. Mine would just stop running and choke to a stop, then start up a few minutes later and run fine until it stopped again. Turned out to be a very dirty fuel filter even though it did not look that bad and the site glass looked good. Apparently the engine would suck fuel faster then the filter could allow, then when stopped the fuel would catch up and run good for a while. New filter and never had that problem again. That being said and you are sure there is no power to the connector I would check the continuity from the connector plug to the start relay behind the dash. You can test the solenoid by applying 12v + from the battery directly to both terminals on the solenoid. If you can hear it click the solenoid is good. If it does not click, run a wire from the battery neg. and touch the body of the solenoid, if it clicks you have a bad ground, if still no clicks you probably have a bad solenoid. Hope this helps at least a start.
Buck
Buck
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The fuel stop solenoid receives 2 different hot signals, one from the starter (pull in coil) and one from the ignition switch (hold coil).
It will only receive the hot signal on the pull in coil while cranking.
It will get a hot signal on the hold coil any time the key is on, if you are not getting a signal on that wire, it either has bad wiring or a fault in the switch.
Normally when just the Hold coil circuit is bad it will start then die when you let off the starter.
It's sounding more like you either have a bad signal on the Pull in coil or a bad solenoid.
It will only receive the hot signal on the pull in coil while cranking.
It will get a hot signal on the hold coil any time the key is on, if you are not getting a signal on that wire, it either has bad wiring or a fault in the switch.
Normally when just the Hold coil circuit is bad it will start then die when you let off the starter.
It's sounding more like you either have a bad signal on the Pull in coil or a bad solenoid.
NIW I discovered in my problem with this issue that there are 2 versions of the wiring harness. On my machine and the wiring diagram the shows the white wire from the from the relay splits and goes goes to both sides of the solenoid ( hope that made sense ). In fact from the relay connector there are 2 wires ( one large and one smaller) at the relay running to the solenoid. No hold signal showing and none found. Both solenoid and injector box ( the proper name escapes me ) are spring return and do not require the pull signal. This maybe a difference between the 2 harness'. Also there are 2 versions of the controller. Mine is smaller and has no pigtail connector and one bolt hole, the other is larger, has about a 4 inch pigtail connector and 2 bolt holes. Somewhere along the line, Kubota made a design change during the B7800 production run. The serial number maybe of some help.
Buck
Buck
BuckBone, Its not the fuel filter. Ive already swaped-out thinking that was it. I removed the fuel solinode thinking it was it. I applied 12v and cliked every time. Put my finger inside where solinode mechanism allows fuel to flow thru. It starts and runs as long as my finger inside fuel pump. Put it back and it gave me problems again. My kubota would not start for a many days and then one day it started. Ran for along time with no problems. It started having same issues. I thought it was the relay switch from the foward and reverse. I thought it would get stuck fron dirt or mud so I jiggle pedal. I thought that was the magic trick. Worked muiltiple times. Now it stops and it takes an hour before it kicks on again. Here recently it died on my wife, it took a couple of hours sitting there. Started and then I decied to put it up untill issue is resolve.
North Idaho Wolfman
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I-R-S you need to give me the Serial number so I can tell you which wiring version you have and which Relay or OPC controller you need to replace.
North Idaho Wolfman
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Not possessed, just electronics on the verge of complete failure.
If it's not cutting out while running, it could be as simple as a failing relay for the fuel solenoid.
or it could be the OPC (occupancy computer)(fancy box of relays) that's failing.
You can test the relay and if that tests good then replacing the OPC is the next best option.
If it's not cutting out while running, it could be as simple as a failing relay for the fuel solenoid.
or it could be the OPC (occupancy computer)(fancy box of relays) that's failing.
You can test the relay and if that tests good then replacing the OPC is the next best option.
Thank you all the info. Finally had to take the dash of the tractor. As I was taken it of, i noticed when removing wires to disassemble dash that wires when moved would activate the fuel solinode. futher messing with wire, found out it was the tractor control box has a short. I tried to order but it would be two weeks before I receive the part. So I jiggle wire till trator stayied running and I epoxy the wires. Its running fine now. I will order the part but until then, Running fine.
TY
Good that you know the solution. Maybe run the existing repair until the problem appears again?
I had a different, but somewhat similar, problem with the control on my wood shop cabinet saw. I ordered a spare magnetic switch, not knowing what was inside, then took it apart and reassembled it, and it works fine. Decided to keep the new one as a spare and use the original until it fails again, then trash it.