Starter shorted out....

Ok guys, kinda baffled here. I was working the 12V 4020D 1967 this weekend to plant some clover. Got done and parked the tractor (shut it down) so I could clean the drill out. I come back out after supper and I start it back up and proceed to put the drill away and turned off the tractor. It wouldn't stop running...I moved the throttle all the way up and it was like chugging really slow. I moved the throttle back to run and it took off again. I tried this several times and got the same results. I turned the fuel off at the tank and tried to "clutch it" as I was not sure what was happening and thinking maybe a fuel issue, but wasn't really sure. At this point I saw smoke coming from the starter. I ran to get a wrench and pulled the cables off the batteries and they were hot....the negative cables. It stopped finally and smelled of burning electrical....the starter was dripping...
I went out yesterday and hooked the batteries back up and nothing happened. I hit the starter button and the starter chugged slowly again and the starter continued to run again until I removed the battery cables.
This is a "new" Iskra starter ordered in December. I have had no other issue with it until this point. I had to clean the battery connections that were corroded Saturday morning before I started and that is all the work I have had to do to the tractor recently.

So what could have happened here? The starter seems like it is shorted internally. I am just sort of baffled here. What part of the electrical system could have caused this? The batteries, the battery cabling (I asked about replacing this earlier last week) or could it have been something with the starter itself? I have heard great things about these starters from others so I am looking for any help here...

The starting system is as follows.....

starter button to solenoid mounted on side of dash to solenoid mounted on the starter as is recommended here for proper hook up.

Thanks guys and sorry for all the questions lately...trying the best I can right now with the cards dealt. Your help is always greatly appreciated.

Kris A NC (now IN)

It's not the starter that is shorted, it's the solenoid that is welding it's contacts closed every time you use it. Put on a new solenoid and your problem should go away. Good starter, imagine running all that time with the engine running and it's still working. Happens on occasion so not unheard of, but thankfully it's rare to see this.

Which Solenoid? The one mounted to the starter or the Aftermarket I put on that sends power to the starter mounted solenoid?

thank you for your response!

(quoted from post at 07:09:27 04/14/14) Which Solenoid? The one mounted to the starter or the Aftermarket I put on that sends power to the starter mounted solenoid?

thank you for your response!

Click to expand...

The one that piggybacks right on top of the starter.