The Stovebolt Site Forums The Shop Area The Electrical Bay voltage drop?

I'm having trouble with hard starting, hot or cold with my '46, 216, 6 volt. I did a tune-up after the condenser went bad and no change. The po put a kill switch on the firewall with about 5 feet of cable from the battery to the switch, then to the starter. Could this cause enough of a voltage drop to make for hard starting? Is there a resistor in the starting circuit that could go bad? Thanks for any ideas. Jacques

When you say hard starting, do mean that the starter is not spinning quickly ? Or is the starter spinning nicely and the truck just won't start ?

The starter spins like I think it should, from what I can remember from past 6 volters I've had. One other thing, sometimes when I'm crankin' her over, the needle on the gas gauge drops to E when the starter's turninin'. I'm wonerin' if there's not enough juice to get a good spark. Thanks, Jacques

If you can get your hands on a voltage meter, check the voltage on each side of that cut off switch while someone else cranks the motor., That will tell you if you are losing any significant voltage through the switch.

Also, I use 2/0 gauge battery cables with my 6 volt battery and starter. I am not sure what size you have. Make sure you have a good grounding strap with clean connections between your frame and the block..

Thanks for the help Bill. I may just eliminate that kill switch completly and make the connection with some of that 2/0 cable, then there'll be no doubt. jacques

I think it is pretty clear that you have a significant drop across the extra cable when using the starter. The gas gauge is good evidence to that. For a test, you could run a wire directly from the battery to the coil, it doesn't have to be of a heavy gauge(16 would do), and you will see the difference in starting. Of course, you would have to disconnect the test wire to stop the engine.

Sounds good. Thanks Nix, Jacques

SHould be no more than .2 volts drop max per connection.Clean all grounds to bare metal and coat with dielectric grease.

I replaced the positive cable from the battery to the starter with "2/0, 2 ought" cable. The po had about 3 feet of 4 ga cable going to a kill switch on the firewall, then about 2 & 1/2 feet of 6 ga cable going from there to the starter. I couldn't believe the difference. The starter now spins like a 12 volter. Thanks to Tom Kelly at Kelly Marine on the bayou in Jeanerette for pointing this out to me and makin' up a new cable for me.