Wires heating and melting going to battery????

Sun Nov 17, 2013 11:51 am

I have a 1951 farmall cub. Im having trouble figuring out why my battery cables are heating up and eventually melting the wires. The guy I bought it from said he converted to 12 v system. I think he might have something backwards and could be causing my problems. The hot side of battery or positive is going straight to starter and the ground goes straight to the tractor. any help would be awesome. you guys always help me with my problems im sure you wont let me down. Thanks from Louisiana!

Re: Wires heating and melting going to battery????

Sun Nov 17, 2013 11:56 am

Its a positive ground system , its backwards however that alone would not melt the battery cables.

Re: Wires heating and melting going to battery????

Sun Nov 17, 2013 8:18 pm

So my negative should be going to my starter????

Re: Wires heating and melting going to battery????

Sun Nov 17, 2013 8:27 pm

In converting to 12 volts, the PO probably changed to negative ground. You need to determine exactly what you have before going forward.

Re: Wires heating and melting going to battery????

Sun Nov 17, 2013 10:46 pm

when I bought my 51 Cub it was wired backwards and it ran I switched to positive ground and no other changes, my battery cables never melted, then is a difference between 6 volt cables and 12 volt cables and since yours is a 12 convert maybe the 6 volt cables are still there :idea: , however still your cub should run pos gronnd or neg ground so my guess you have a short somewhere or bad cables.


link to a similar battery cable post

viewtopic.php?f=1&t=39074&p=322352&hilit=+positive+ground#p322352

Re: Wires heating and melting going to battery????

Sun Nov 17, 2013 11:00 pm

It won't hurt to use the six volt cables with a 12 volt battery since 6 volt cables are heavier than 12 volt cables.

Re: Wires heating and melting going to battery????

Mon Nov 18, 2013 10:19 am

What size cables do you have? The original size battery cables are heavy enough you should be able to put a dead short on the end of the battery cables and still carry the current till the battery goes dead. Check your wiring, It originally would have been one wire from battery to frame of tractor (originally side of battery box), and other battery wire to starter. Then a smaller wire from the starter stud to the amp meter and another to the generator. If it is the big wire from the battery melting, check for shorts, especially where it passes the clutch pedal. Since it was converted to 12 volts it was most likely done wit an alternator, in which case it should be wired similar to this. diagram compliments of Farmall Bob Mehlville.

Image

Re: Wires heating and melting going to battery????

Tue Nov 19, 2013 9:15 am

Check the area where the battery cable is routed next to the clutch pedal.

Re: Wires heating and melting going to battery????

Fri Nov 22, 2013 4:19 pm

Barnyard wrote:It won't hurt to use the six volt cables with a 12 volt battery since 6 volt cables are heavier than 12 volt cables.


so very newbie here but
I just threw on some battery cable from the auto store for the pos ground ( and in my other post kicked it off and now the cub will not spark at all)
can this 12 volt cable cause me problems,
Thanks

Re: Wires heating and melting going to battery????

Fri Nov 22, 2013 5:23 pm

The cables for vehicles are not really rated by voltage but by gauge. The so-called 12 volt cable is a smaller gauge (higher numerically) than is cable suitable for 6 volt vehicles. For 6 volt Cubs, 2/0 cable is ideal. For 12 volt, #4 might be adequate.
None of this applies to wiring for buildings.
Battery cables experience maximum loads for only brief periods of time and it is assumed that significant cooling times will occur between periods of heavy use. Cables that are too small have significant voltage drop and the drop is directly proportional to the amperage that cable is supplying at the moment.