Small Battery Cables

joeyfast13 · Post by **joeyfast13** » Mon Feb 27, 2012 10:56 am

I have a m38a1 that was partially converted to 12v and i finished it.. Tore down the motor to put gaskets on it and new clutch..
I have double checked the timing gears..
It seems to turn over slow and im thinking that its not starting because of the small battery cables.
Am i right?
If the starter is pulling all the power from the small cables wouldnt that kill my coil power?

Post by **wesk** » Mon Feb 27, 2012 1:03 pm

The cables must be of adequate gauge for the starter voltage. Cheapy 12 volt 6 gauge gauge cables are not even adequate for 12 volt.

If you are running a 12 volt starting system then you should use at least 4 gauge.

If you are running 24 volt the 4 will work but the military used the heavier 2 gauge.

Oldsalt · Post by **Oldsalt** » Mon Feb 27, 2012 1:10 pm

Small battery cables are typically not an issue on 12v systems, even if you are using the original cables from the 24v system. There are lots of other things to look at first. Does your battery test good? Are your battery cable connections clean and tight? Is your timing set correctly? Spark plug wires in the correct order? Any chance your starter is binding against the flywheel?

is your timing set correctly? Are your spark plug wires in the correct order? Assuming you did change the 24v starter for a 12v starter, is it good? Is it perhaps binding against the flywheel?

joeyfast13 · Post by **joeyfast13** » Mon Feb 27, 2012 7:10 pm

Jeep ran great before i tore it apart and starter worked great. Use to start up real easy. Ive had a full a full charged battery in it and have hooked jumper cables negative on negative and positive on the starter hot post didnt changed how it turned over and jumper cables are pretty small and the felt warm. The only thing i changed as far as electrical was the jumper cables i had the big ones on it before when it ran.. But i put smaller ones on as was wondering what you guys think? When it warms up im gonna get outside and start tinkering with it.

Oldsalt · Post by **Oldsalt** » Wed Feb 29, 2012 1:30 pm

When you say jumper cables, do you mean the battery cables? If you are feeling heat then you definitely have a resistance. If that heat is in a specific spot, like the battery terminal then you might have a problem with a dirty connection. Cables that have those clamp on terminals are a frequent cause of problems because corrosion can form in those clamps. If you still have the bigger cables, putting them back on is an easy test to see if it helps.

artificer · Post by **artificer** » Wed Feb 29, 2012 2:26 pm

If the engine has been out you need to be checking all the ground cables are clean & have been re-installed. The best way to quickly establish whether it is a starter related problem is to jump directly from the battery negative terminal to the starter body or attaching bolts. Then try & start.
Off course you can also use your automotive multimeter <$20 to test all of these things.