Cables to the battery

[Fred Mc]

On my GM PD4106 the STOCK configuration has the starter positive lead connected to the batteries thru a connection on the engine bay bulkhead. |\So on the positive post on the starter there is the cable which connects to the bulkhead connection (batteries) and one that goes to the alternator.
I changed the battery location some time ago and moved the batteries into the old air conditioner pump location which puts the batteries a few feet closer to the starter. And in doing so I ran the positive battery cable to the same stock connection on the bulkhead. Thus this connector feeds both the starter and the rest of the bus.

I am now troubleshooting for poor starting and was wondering if I can go directly to the positive post on the starter from the batteries. This would then give me direct connections both to the positive and negative posts on the starter eliminating any connections. I would then still have a cable which goes from the positive post on the starter to the bulkhead connection. In reality I am simply moving the positive battery cable  from the bulkhead connector to the starter.

I realize this probably will not solve my starting problems but by reducing the number of connections you eliminate trouble spots.

Am I missing something.

[luvrbus]

Check the ground to the starter 1st I hook both of those directly to batteries the + and - GM buses give me a fit with grounds fwiw

[chessie4905]

Did you disassemble the connections at the bulkhead? Years of salt and others can cause corrosion to build between the cable ends and stud. Also have batteries load tested unless they are new. Many starting issues end up in being cause by weak batteries.

[Iceni John]

I suggest keeping the number of individual cables between the batteries and the starter to a minimum (the fewer the connections, the better), and keep them as short and fat as possible.   Are you going to use a main battery disconnect switch?   If so, run a 4/0 from each battery positive to the switch, then one 4/0 to the starter positive.   Use closed-end tin-plated lugs, crimp them properly with a good circumferential crimper like the FTZ 94284, heat-shrink the ends so moisture cannot get in, then you should be good for many years.   You can either use a VTE through-wall 500A pass-through connector, or if there's no cable movement you could just grommet a hole in the wall and reinforce the cables where they pass through (two fewer connections per cable that way).   Don't use stainless nuts or washers if high currents need to pass through them, but they're OK to use as simple mechanical hold-downs for the lugs.

If you have positive ground, these same basic principals still apply!

Have fun, John

[brmax]

 I found many times the starter ground post is covered with green corrosion "between" and inside the housing making a weak point there, believe it or not!
Good day
Floyd