B21 won't stay started. Suggestions?

[HarlanOR]

Hey there tractor people!
My Kubota B21 turns over and starts, and it will stay running as long as I am holding the key in the starting position, but as soon as I release the key, it shuts down. The battery is brand new and was changed to eliminate any battery connected issues.
Any suggestions?

 

[85Hokie]

Sounds as if your fuel solenoid is cutting out when you let go of the key.

Can you place a volt/ohm meter on that solenoid and verify that? Basically unhook the connection to the solenoid - place your VM there and see if voltage is there when key is turned then released.

Another possibility is you key switch has played out.

 

[North Idaho Wolfman]

This sounds like the hold coil on the run (stop) solenoid has bit the dust.

 

[Dave_eng]

I would follow NIW's suggestion and add to check the 5 amp fuse which feeds the hold coil on the stop solenoid.

Also do the checks for the two internal solenoid coils.

Dave

 

[Henro]

This sounds like the hold coil on the run (stop) solenoid has bit the dust.

The symptom you describe is exactly what I experienced with my BX2200.

Cause was as Wolfman says, hold coil in the fuel cutoff solenoid had failed. But as Dave said, a blown fuse feeding the hold coil could also be the cause. In my case, the fuse was blown due to the failed hold coil...