electrical short

Tractor ran fine for a while. Now when I try to start it the starter switch is getting very hot. I figure I have a short somewhere. Have checked all the battery connections they are fine. replaced starter switch. When I crank the battery the starter switch begins to smoke. Any ideas what to check for?

Thanks to all who help
bill

The kind of tractor is pretty important, but here is some info: (be sure it is out of gear and brakes set)
There may be a short, but less likely.
The most likely is a combination of a stuck starter (jammed in the flywheel)and a failing starter switch.
Loosen the starter bolts and shake the starter a bit, then re tighten, and try it. It may be OK, but it will need a starter switch soon.
Bypass the starter switch with heavy gauge jumper cables (not booster cables) if the starter heavy switch is connected with cables to the starter on a stud and bolt. Touch the jumper to the starter terminal directly on the starter. (It will spark big, but should spin it)
If this works it needs a new switch.
If it has a switch mounted on the starter, and no external wire going in, then remove the switch, and use a jumper to the stud/lump sticking out.
Again it is a bad switch if it works.
Starters draw 400 to 500 amps on 6v and need great connections to keep from heating wires and switches. Be sure all cables have conductors in them as fat as a first grade pencil. (not the insulation, the copper!) Let us know what you find. JimN

A smoking starter switch could be caused by (among other things) a bad or stuck starter. Once you insure its not mechanically stuck/jammed to the flywheel gears thats causing the smoke, then youre still left with a bad switch or bad starter or cable or connection problems, but since the switch was replaced Ima thinkin more the starter itself (if its NOT a cable or connection problem).

If its a saddle type mount on the starter switch, the copper button/post that comes out the starter may be burned or corroded or carboned up or simply worn down too short n arcing causing problems. If its the stand alone up on the tractor 2 terminal push switch, while the switch may itself be bad, thats NOT the problem described before...

After you remove n clean n wire brush each n every battery n switch n starter n ground connection and if it still smokes, see if when you engage the switch the lights (turned on if it has any lights) dim way down badly and/or the battery voltage drops drastically????????? IF SO (assuming its NOT mechanically stuck/jammed) I SUSPECT THE STARTER IS BAD. HOWEVER if the lights dont dim much or the battery voltage dont drop much n the switch smokes, Ima thinkin more a switch problem, but a new switch should have cured that ????

The starter could have worn bushings allowing the armature to drag the field poles, that will cause excess current draw perhaps causing a switch to smoke and/or the starter to get real hot

let us know

John T

It could just be something as simple as a bad ground..if you have a bad ground it will cause problems..make sure the ground cable is touching metal completely and not on paint or rust

(quoted from post at 22:27:31 10/21/08) It could just be something as simple as a bad ground..if you have a bad ground it will cause problems..make sure the ground cable is touching metal completely and not on paint or rust

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Mine would groan itself into starting from the time I had bought it. Didn't pay it much attention because it was my first tractor and just figured at 40 years old, it should groan a little. Had to jump it one day and there was no real difference in the speed of cranking that I thought should be there.

The ground cable was real hot. Correded on both ends, but when I skinned a little insulation, the corrosion had worked it's way most of the way through the cable. Replaced both cables with sealed units from the parts store and it's like having a new tractor (ugly new tractor).

Good Luck,


Dave

Just had the same thing happed to me.
It was the starter clean the brushes and armature
and what other crude is in there.

If switch is smoking, sounds like the contacts are burnt. If the switch comes apart, clean the contacts and see if the smoke disappears. Could also have problems that others described, but I would start with the switch.