Massey Harris 44 negative ground conversion won't start

[chemtimh]

Had to get a new alternator on a 12V positive ground MH 44. I did a quick negative ground conversion by swapping the leads on the coil and the amp gauge and the battery so I could get a new 12V negative ground alternator with an internal voltage regulator. I disconnected the old voltage regulator. Now when the starter button is pressed the starter makes a single click and the big cables (even the battery frame ground) get very hot in just a second or two, and so does the starter.

I removed all the big cables and bought new ones, cleaned the surfaces and bolts they mount to, and had the battery tested. No diff. Now every wire, big and small, on the tractor is brand new and every connection has been cleaned, even the lights.

Yesterday this was a positive ground 12V tractor that started fine but had a bad alternator. Today it is a negative ground tractor that has a problem getting current to the starter. I did not touch the starting circuit when swapping out the alternators!

Suggestions please. What could cause this apparent overdraw of electricity, and why would it happen on conversion to negative ground?

 

[Agvg]

Would tear down the starter and check brushes and mechanical wear.

 

[chemtimh]

The problem wound up being the battery. It was down enough not to turn the starter, but up enough to test as "good," hold 12.5 volts, and give out a lot of electricity as heat. I replaced it and up she started!

 

[jaxs]

I just hate those type problems. I had 35MF that wouldn't start so I replaced the carburetor,distributer,plugs,plug wires,starter,ignition switch and it still wouldn't start. Ended up the fuel was turned off at sediment bowl. Nother time it was making a terriable racket while running. After asking on all the forums and replacing several things,I discovered the fan blade was hitting shroud. I have a whole stack of shop manuals and not a one mentions either of those as things to check. Glad to hear you found your problem.