Starter goes on its own.

I am in need of a little help.

I have a front mount distributor 8N. 12V.

The other day, I went to start it and nothing happened when I hit the starter button other than a few sparking sounds from down by the starter. I tightened the crimp on the battery to solenoid cable at the solenoid and it then worked fine. I ran it and shut it off for a little while, it worked fine. An hour or two later, I went to start it an got a similar sound, but this time up by the battery. The connection at the battery was a really cheap cable/connector and was a little loose. It was arcing and melting the connection. When I moved that cable and it came into contact, the starter started cranking. I couldn't get it to stop. I flipped the switch on and it fired right up. I drove it the short distance to the barn and shut it off, The starter kept on cranking. I cut the battery cable to get it to stop.


All that to ask what is wrong. I thought it might be the solenoid so I replaced that(TSC) and both battery cables (McMaster), and it did the same thing as soon as I touched the ground to the battery. Then thinking it might be the starter switch, I disconnected that wire at the switch and it still did it. What am I missing? Any ideas what might be wrong?

Andrew

Sounds like the solenoid is somehow getting 12V without the button being pushed. When it was arcing, you may have melted some insulation on wires and it is touching another 12V wire.

Check the wire from solenoid ssto the start switch, it may be grounding out.

I will check for that again tonight. I thought I checked for that Saturday when I was trying to get it started, but I might have missed something.

Thanks.

Andy......the 8N's starter solinoid is activated by grounding the little middle terminal with the BIG thumb switch by the tranny shifter. Many times yer #12 brogan (boot) will kick the wire going to the BIG thumb switch and crack and SHORT the wire to tractor chassis ground. ...ie... carefull where you step, eh? It should be intutively obvious replace the wire with #14 stranded automotive wire. (3-ft?) Couple of other helpful hints: 1) pull the 8-in screws and slip the starter motor out about 1/2-in. SANDPAPER both sides of the gap. Will really speed up the ol'starter motor. BTW, even 6-volt starter solenoids on 12-volts are quite rugged and seldomn need replacing. Yeah, sometimes the battery clamp won't clamp, little cleaning will fix that. Yeah, the 4-nipple front mount kenn bee a pain. Me? I'd unsnapple the capple and stick the corner of $1-bill (cheap) between the points (0.015) and pull. Polish the INVISIBILE CORROSION away. ..........HTH, electrical Dell

Ok, I looked it over when I got home. I fully removed the wire to the starter button. It still started on its own. I the also removed the wire up to the rest of the tractor. It still started.

Does that mean it's a bad brand new part or could there be something else going on?

Thanks for all the help.

" I thought it might be the solenoid so I replaced that(TSC)"

TSC is good place to buy chicken feed and shirts. Not so good for tractor parts.

I'd say the chances of a defective solenoid, or more likely, an incorrect solenoid are highly likely.
75 Tips

Where should I buy a new solenoid?

Correct me if I'm wrong, but didn't you say that this was happening with the old solenoid as well?

Yes. I didn't take all the wires off he old one while it was
attached like I did with the new one, but after a carful check, I
didn't see any spots where those wires were shouting out.

Tell them you need a solenoid for a 8N 12 volt negative ground.

Get it here or from nnalert's.
75 Tips

(quoted from post at 08:43:54 04/04/17) Tell them you need a solenoid for a 8N 12 volt negative ground.

Get it here or from nnalert's.
75 Tips

Click to expand...

and wire in accordance with one of JMOR"s wiring diagram, it may be wired wrong.

(quoted from post at 07:23:47 04/04/17) Yes. I didn't take all the wires off he old one while it was
attached like I did with the new one, but after a carful check, I
didn't see any spots where those wires were shouting out.

Click to expand...

So if happened with the old solenoid and is doing it with the new solenoid, I'm leaning towards a wiring issue. Unless both solenoids are incorrect or both have the same failure.

Simple enough you have a shorted starter solenoid. Your not the first and won't be the last. Many, many years ago, neighbor down the road has a Ford that started cranking at about 1 AM. A few seconds later, long enough to go out to the car, it stopped. Back to bed. Cranking starts again. Run back down stairs. It stopped cranking. He stood there long enough for it to start cranking again. He pulled the cable and went back to bed.
I had a '65 Mustang that did it to me at a gas station. Pulled up, shut it off, getting gas and it starts cranking. Turn the key on trying to get the starter to spin out and no such luck. Pull the cable and it finally quit.
Interesting also is the tapered battery post on top post batteries. Designed so it is suppose to be possible to twist the cable off in case of an electrical problem. Most everyone over tightens the clamp and twist removal is not an option easily exercised. Might also help to carry a battery bolt wrench near the battery or install an electrical disconnect switch on the neg side.