Have I killed my battery?

[Nuvo]

A fews days ago I connected an electric tyre pump using the cigarette lighter plug. The spring loaded ground contacts started sparking and glowed bright orange before vapourising in a matter of seconds.

Days later I returned to the car to be greeted with a clicking starter motor solenoid on the turn of the key.
Its clear that the battery has been discharged from the short circuit. Can a relatively new battery recover from this when smart charged or have I killed or significantly shortened the life of the cells?

[martinws]

Shouldn't cause an issue I wouldn't think, a bit weird that there was enough current to make the spring contacts glow without a fuse blowing though.

[Nuvo]

Thanks for the reply. The good news is the battery accepted a full charge, the not so good news is the starter solenoid still can be hear engaging but the motor fails to spin. So at this point I'm thinking the motor is sticking.

Is this the most probable cause and is there anything else I should check over? I've still to look over the schematics to familiarise myself with the wiring and components used in the starting system.

[John.]

Assuming everything else is good, starter is likely culprit.........but you'll need to check everything else!
Poor connection causing high resistance at any point in the feed or earth circuits would explain your issues. Worth checking your earth strap connections between engine and body, and body to battery. Also positive between battery and where it bolts to solenoid.
Braided cables between solenoid and motor can also perish but as the solenoid earths through the motor and you're getting a "click" then this is unlikely.
If you can get someone to tap the starter while you try and crank it, if it turns over then sticking brushes/bad connection inside motor is likely.

[macspring]

If you think your starter is original, it would be worth having it refurbished assuming the car is a keeper.

Admittedly not the additional expense you want, but it will be one less item to mess you around, and give you piece of mind.

[Nuvo]

My suspicions are that the brushes are the culprit as all connections check out, I hope to confirm this tomorrow.

Thankfully I've got a spare working motor which I'll plug in under the car to test the circuit, after trying John's suggestion of tapping the starter body while a helper turns the key.

I'd like to have the current one refurbished to serve as spare.

[Nuvo]

It seems that I'll fallen at the first hurdle.

So I've spent the best part of this morning trying to remove the nut from the starters positive stud but the threaded stud can be seen to rotate with the nut.
I tried soaking the stud in penetrating fluid and going over the threads with small brass "toothbrush". I tried tightening the nut a little and then shocking it loose to no avail.

I really want to avoid shearing the stud if at all possible. Can anyone help please?

[John.]

What about using a hacksaw or dremel to cut a slot in the stud and hopefully a screwdriver can then be used to hold it?

[Nuvo]

Thanks John, that's good thinking. I'll give that a go.

[Nuvo]

What about the possibility of using either of the following tools to act as a counter hold? Would these damage the threads or not?



or

[John.]

What about the possibility of using either of the following tools to act as a counter hold? Would these damage the threads or not?

Will depend on how tight/seized the nut is I would think?