John Deere 5210 Won’t Start. I have a John Deere 5210, 3 cylinder diesel with just over 2000 hours that I bought a couple of years ago. It ran well until last fall. Actually, it still runs well… when it runs.
Here’s what I have. I jump up on the tractor, turn the key to Start, and the tractor fires right up. As soon as I let go of the key to Run, the tractor quits… just as if I had turned the key to Off. As long as I hold the key on Start (I know… not a good thing), the tractor continues to run. But here’s the catch… once the tractor warms up a little bit, I can let go of the key; let it go to Run, and the tractor continues to run.
It doesn’t seem to matter what the ambient temperature is. Once the engine warms up a little, it starts and runs fine.
Other info: I do hear a click at the fuel solenoid when I turn the key from Off to Run.
The cold start advance is NOT the issue with your tractor “dying”.
It’s purpose is more for emissions control than as a starting aid.
The sensor (with 2 wires) sometimes fails and blows the fuse that powers it and the fuel solenoid and fuel pump (if so equipped).
If the sensor shorts and blows the fuse, the engine stops, and that’s it ’til the fuse is replaced and the cycle then repeats.
If you have done as TimS told you and unplugged the (2 wire) sensor and it starts and later dies, that further proves the cold start has nothing tom do with your problem.
Once again, the “cold start solenoid” MAY help a little with a quicker cold start, but as soon as the engine is running, it does NOTHING but (hopefully) make the exhaust a little cleaner.
Your problem is one of two things, either the fuel shutdown solenoid is “flaky”/thermally sensitive, or something in the electrical circuits of the tractor is cutting power to it.
Try this… connect an unpowered test light between the terminal on the fuel shutdown solenoid and chassis ground, does the light stay on when the engine “dies”, orm does it shut off indicating a loss of power?
You can also connect a jumper lead from a 12 Volt source to the fuel cutoff solenoid, and verify that the engine continues to run with as long as the jumper is connected.
If that works, you’ll need to figure out where power is being lost in the “run” circuit.
Might be as simple as a failed “ignition” switch that’s failing to keep the fuel solenoid energized as the key returns from “START” to “RUN”.