Two wire selenoid does not click when key is turned on. Tester indicates no power. Direct battery power chatters selenoid. I have tried the following: Installed new key switch. Removed and cleaned all fuses in fuse box. Checked relay per instructions in manual, checked good. Checked OPC Timer per manual, checked good. Checked safety switches and all seemed good. In fact, starter turns over fine. Battery and ground seem good. Still no power to open fuel to engine. Do not know what else to look for at this time. Other ideas would be helpful. Thanks!
L5030, No power to fuel selenoid.
- Thread starter Taildragger Fly Boy
- Start date
I'm not sure of your model's particulars, but "many" two wire fuel cut off solenoids only "click" when the key is turned to the off position after running.
That is, the normal state for the fuel valve is OPEN (solenoid de energized) When the key is turned to OFF, the controller sends 12V to the solenoid for several seconds to shut off the fuel, and shut down the engine.
The Fuel shut off CONTROLLER is the key component.
The reason fo this configuration and method is due to the large current requirement for a solenoid that will pull open a fuel shut off valve.
Your system may be different. But check with the wiring schematic and see if there is a controller. A quick and dirty check would be with a VOM and watch for voltage at the solenoid for a few seconds just after the key is turned to off.
Remember, Your system may be different. Check the Wiring Diagram!
That is, the normal state for the fuel valve is OPEN (solenoid de energized) When the key is turned to OFF, the controller sends 12V to the solenoid for several seconds to shut off the fuel, and shut down the engine.
The Fuel shut off CONTROLLER is the key component.
The reason fo this configuration and method is due to the large current requirement for a solenoid that will pull open a fuel shut off valve.
Your system may be different. But check with the wiring schematic and see if there is a controller. A quick and dirty check would be with a VOM and watch for voltage at the solenoid for a few seconds just after the key is turned to off.
Remember, Your system may be different. Check the Wiring Diagram!
Kubota books has an excellent pdf WSM for L5030. 619 pages of a wealth of information.
I think toomany describes the proper operation of the solenoid which is power when key is first turned to OFF. Try your check with key ON then turned to OFF. The component name " Engine STOP solenoid is likely the best cue as to how it works and when.
From what I see the engine stop solenoid has a relay to power it. This is likely the click you hear rather than the solenoid when things are all OK
You could swap another of the tractor relays into the engine stop position and see if things change.
Internally, the stop solenoid has two wire coils. It may have an internal switch but I am not certain as some Kubota stop solenoids do and others don't. I would need to spend considerable time with the WSM and know more details about your tractor in terms of Cab or no cab, hydrostatic trans or manual, etc
One coil is stronger than the other.
Two coils, working together, pull the solenoid plunger in and then the weaker coil holds the plunger in.
Can the stop solenoid rod move?
Check the relay situation, whether power is present when the key is turned from ON to OFF although this test may require the engine to be running. Check and the solenoid plunger next and then come back with some news.
Dave
I think toomany describes the proper operation of the solenoid which is power when key is first turned to OFF. Try your check with key ON then turned to OFF. The component name " Engine STOP solenoid is likely the best cue as to how it works and when.
From what I see the engine stop solenoid has a relay to power it. This is likely the click you hear rather than the solenoid when things are all OK
You could swap another of the tractor relays into the engine stop position and see if things change.
Internally, the stop solenoid has two wire coils. It may have an internal switch but I am not certain as some Kubota stop solenoids do and others don't. I would need to spend considerable time with the WSM and know more details about your tractor in terms of Cab or no cab, hydrostatic trans or manual, etc
One coil is stronger than the other.
Two coils, working together, pull the solenoid plunger in and then the weaker coil holds the plunger in.
Can the stop solenoid rod move?
Check the relay situation, whether power is present when the key is turned from ON to OFF although this test may require the engine to be running. Check and the solenoid plunger next and then come back with some news.
Dave
When working properly, selenoid gives loud click when key is turned on. Relay behind instrument cluster can be felt closing. I have swapped the identical glow plug relay with the selenoid relay with no change. When working properly, full voltage pulls the selenoid open when the switch is turned on. Lower voltage then holds the selenoid open down the second wire. I have already proven this as the problem first started on an intermittent basis. Sometimes power would be provided to the selenoid and then, next time, it would not be there. Repeated turning of the key had eventually started the tractor and that key turning had been something I repeated until I heard the loud selenoid click. It is now to the point no power makes it to the selenoid, no mater what I do and even after installing a new switch as a possible solution. This far, I have been unable to determine where the malfunction is taking place.
Remember we are trying to help not criticize you. We need to engage in a meaningful dialogue as you know your machine far better than anyone else can.
I was wrong in stating the solenoids job is to stop the engine. Just the opposite
I have studied and marked up one model's starting system wiring.
The red line is 12 volts direct from the battery, through a fuse #6 to the open contacts in the engine stop relay. This is power waiting to be switched on at which point battery power flows through the blue marked circuit to to the left hand coil in the engine stop solenoid.
Turning the key to Acc, On, or start positions sends power through the yellow marked circuit through fuse #8. This circuit does two actions. It closes the relay contacts by powering the small coil in the relay and now battery direct 12 volts is going to the engine stop solenoid LH coil through the blue marked circuit. The second action is to provide 12 volt power from the key switch to the right hand coil in the engine stop solenoid.
Would you have as test light like this one?
I do not believe the voltage to the engine stop solenoid changes. The pull in power of the two coils in the solenoid itself is different but both coils see the same 12 nominal volts.
From memory, you do not find any sign of 12 volt power on either of the two wires to the engine stop solenoid. This means that either two fuses are blown, #6 and #8 or there is a problem in the key switch
Can you please give me more specifics about your tractor so I can study the correct wiring diagram.
The WSM lists these different 5030 models and has a different wiring diagram for each of them.:
Manual Transmission ROPS type
Cabin type
GST model
HST model
This wsm material shows battery voltage sent to both solenoid circuits
This formal check of the relay may identify if there is a wiring problem. Squirrel chewed etc.
Dave
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Interesting fuel circuit, no safety switches for engine shutdown at all, only for start up.
Dave's on the money for the testing, checking fuses/switch/relay etc., as there is only the fuses, key switch, relay and solenoid in the circuit (if Kubota's diagram is correct, they have been known to have faults in some of them).
Dave's on the money for the testing, checking fuses/switch/relay etc., as there is only the fuses, key switch, relay and solenoid in the circuit (if Kubota's diagram is correct, they have been known to have faults in some of them).
My tractor is an HST Model. I do not have a test light but will gladly obtain one to try to help solve the problem.Thanks for input thus far.
I am concerned that there could be a fuse somewhere I am not finding. The only fuses I have found and checked, thus far, are located in a small black fuse box below the panel and to the left of the steering wheel. All my checks have been done using a Craftsman multi-meter.
Both glow plug and fuel selenoid relays test good, (I had interchanged them as a cross check as they are identical). Test was performed according to instructions given in Dave's post. Thanks.
Still trying to resolve this issue. My L-5030 HST, Non-Cabin Model has a different wiring diagram than the one Dave provided. My parts man says an OPC Timer may play a part in my selenoid chain. If anyone has a copy of the correct diagram, that would be helpful in knowing where to search further. Colder weather and Christmas Season has prevented my research from making headway. Being new and unfamiliar with this forum, I may now be out of the loop for future follow-up but appreciate all that was previously suggested. I have, thus far, not found the problem within the suggestions given.
Thanks!
Thanks!
There are diagrams for the different models in the service manual, they are very similar, as previously noted it appears the interlocks are only for starting, not running, if the diagrams are correct.
Have you checked all the slow blow fuses as previously noted, particularly the 30A one?
Ideally pull each individual small blade fuse as well and check with a multimeter.
If the 5A control fuse and the 30A main fuse aren't blown, check for voltage at the key switch IG1 terminal, then at the relay. If you have power at the relay, but no relay action, check the ground wire to the relay.
Have you checked all the slow blow fuses as previously noted, particularly the 30A one?
Ideally pull each individual small blade fuse as well and check with a multimeter.
If the 5A control fuse and the 30A main fuse aren't blown, check for voltage at the key switch IG1 terminal, then at the relay. If you have power at the relay, but no relay action, check the ground wire to the relay.
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I know this post is from late 2017 but some may wonder how my problem was finally solved.
It turns out that there was a short in the wires leading into the OPC Timer. I was finally able to isolate the problem, and separate the wires to prevent further shorting without replacing the timer. Tractor has been working fine this summer and I did not find it necessary to replace the $95 part, at least thus far. Thank you for all who responded and for those who offered to send me a wiring diagram for my actual model.
I read posts from time to time where the solution is never revealed so I wanted to close this one out with my solution, in case others have a similar problem.
My tractor has 3700 hours and has given very little trouble, thus far. This took the longest to resolve but I was unable to devote the time to it during the cold winter.
Thanks again!
It turns out that there was a short in the wires leading into the OPC Timer. I was finally able to isolate the problem, and separate the wires to prevent further shorting without replacing the timer. Tractor has been working fine this summer and I did not find it necessary to replace the $95 part, at least thus far. Thank you for all who responded and for those who offered to send me a wiring diagram for my actual model.
I read posts from time to time where the solution is never revealed so I wanted to close this one out with my solution, in case others have a similar problem.
My tractor has 3700 hours and has given very little trouble, thus far. This took the longest to resolve but I was unable to devote the time to it during the cold winter.
Thanks again!