john deere ltr 166 engine turning over without key in

[miker]

Turned machine off today, solenoid( i think) was still running, pulled one of the wires off..still running, started taking earth lead off the battery, lots of sparks,then starter kicked in, key was out, pulled wiring from ignition...still cranking !!, finally got earth lead off and it stopped

 

Help !

 

Cheers

[GardenKit]

If I read this right, it seems that the engine stopped OK when you turned the key off, but the starter was still spinning. It probably made a whirring noise, but the starter gear had been thrown along the bendix so it was not cranking.

You then pulled the wires off the solenoid, but it made no difference. This indicates that the solenoid contacts have welded internally and proves that it is not being activated from the switch.

You then tried do disconnect the battery and whilst doing so, interrupted the power briefly, allowing the starter send the gear back along the bendix as soon as the power was restored, so cranking the engine.

 

It all points to the solenoid having failed. This is a simple and cheap repair.

[miker]

Thanks gardenkit, yes this is exactly what happened, i replaced the solenoid a few months ago as it failed to engage,so possibly a bad replacement, i will seek out another

Cheers