My starter solenoid melted

[DissFigured]

I was in the parking lot of an Oreily's (Thank God) and I was starting the car and it wouldn't start. It would turn over but it would get weaker and weaker and then it would start cranking faster then slower yatta yatta.

Wouldn't start.

tried again same results. Been doing this for about a week.

I opened the hod and the ground wire had gtten so hot that it melted the solenoid and actually detatched from it with the bolt still connected. WTF?

I got a new one put in and everything is fine.
Anyone know what might cause this?

 

[runawayabc123]

Today I was doing a compression check with my dad and brother. (It ranged 80-105 which was far better than we expected with all the gas in the oil pan.)

Getting on with it, my dad pulled out some old switch with two clips on it to go to the solenoid. (It looked comercial grade from when he was a mechanic.)

When he pulled the switch, the car turned over at a crawl, the wires got hot and it smoked a little (the clip to solenoid). We ended up turning it over with the key instead and all worked fine.

Our guess was just old warn out wiring (although the mustang's wiring is older) or a really dirty contact.

I don't know if this helps much, but it seems simliar.

I am keeping my fingers crossed for you that all is well and will stay well.

 

[2nd Mustang]

Doesn't the hot 12 volt lead go to the solenoid from the battery? Which ground wire are you talking about?

 

[DissFigured]

Hot goes from battery to solenoit, and then on the polor popposite of the solenoid, is a wire that goes to the ground (engine)

The thick black wire on the right on the back of the solenoid is the ground.
It melted right through and became detached

 

[2nd Mustang]

Usually when a wire gets hot, there is too much resistance in the flow of the voltage. Hopefully it was just the solenoid ground lug being loose.

 

[DissFigured]

Well, I got a new one that has a lifetime warranty and appears to be made of a different non meltable material.

 

[dennis112]

Hot goes from battery to solenoit, and then on the polor popposite of the solenoid, is a wire that goes to the ground (engine)

The thick black wire on the right on the back of the solenoid is the ground.
It melted right through and became detached

Hopefully you realize that the thick black wire (found on the right of your solenoid picture) goes to the starter. The system ground goes from the negative side of the battery to the engine block.


There is just too much current being passed through the solenoid. Of course the old solenoid could have been bad and became toast on its own. . . . . . .

If a new one doesn't correct the problem, I would suspect that you either have a bad starter, the motor is locked up for some reason, or you have a loose connection either at the solonoid, the starter, or the battery to block ground.

 

[truck90278]

If a starter starts dragging (worn bushings allowing the armature to slightly touch the field magnets, particularly when hot, the starter will draw excessive amps resultoiing overheating the cables. If the slow cranking continues, especially after the starter gets to operating temperatures, then may need to replace the starter. The other posts hear regarding bad grounds are also correct.