Battery Cables

Roger Harmon

All,

I'm getting a slow warm crank. Some of my cables are 2/0. Do I replace them with 1/0 or 0/0?

R/ Roger.

[Deleted User]

Before you get exited about changing parts find the problem first. Take a volt meter and place one lead on the negative terminal of battery and the other to your starter terminal. With the meter set on 6-volts dc crank engine . If you get more than a slight voltage reading you have bad connections or cables. Check the positive (ground on most Hudsons) the same way only go to the engine block and battery.
And yes the bigger the better on 6-volt cables make sure,
Roger

wano1949

The 6V main cables should be about the size of your little finger (wire size).
A good idea is to run an extra cable to one of the starter bolts to make sure of the engine ground.
Make sure all connections on the grounds and hots are clean and good.

These cars (all 6V, all manufacturers) started good when new and people didn't worry at all
about it.
6V worked well for all manufacturers for a long time. It was adequate for the times.

I put something on here awhile back about driving one while in Michigan in the 70's, 17-25 below zero and no problems. You just had to have a good battery and clean connections.

As the cars get older all the connections (even the small wires) get more resistance in them so it's not a bad idea to clean them periodically, (every few years), and coat them with an electric connection sealer.

Usually it's the grounds which cause most of the troubles.

If all this doesn't work start looking at.

The starter shaft bushings are good, the battery is good, the charging system is good, and then the engine.

PS.
Could someone on here explain why the 6V cables have to be so much bigger than 12V? I know what is required and what works from experience, but not why. lol.

Geoff

Ohms law! Briefly stated, voltage = current x resistance. They are locked in this inextricable ratio. Because 6 volts requires a heavy current to turn the starter motor, you must have a large heavy cable to overcome resistance increase. Passing a heavy current through a small cable causes heat, which increases resistance, which causes voltage to drop between the starter and the battery. For instance, take a simple circuit of a 6 watt, 1 amp light bulb in a 6 volt circuit. This would have 6 ohms resistance. If the wire to bulb was extremely thin, and heated up to give 3 ohms resistance, this would drop 3 volts across the wire, and 3 volts across the bulb, which would glow dimly. Same thing happens with a thin cable to the starter.

hudsontech

A note here to expand what wano1949 said about clean terminals. I had a 1969 Rambler years ago (car make not important here) that was at the time about 15 years old. that had a problem with the alternator light. It would light up a bit, sometimes bright, sometimes dim, but would come on. A thorough check of the electrical system showed nothing. I finally took every terminal I could get a wrench, screw driver or whatever on and cleaned them. Even took the little spade terminals apart and cleaned those. End of problem.

Hudsonly,
Alex Burr
Memphis, TN

StillOutThere

Remove the starter from the engine, clean the oil and grease and especially ALL PAINT off both mounting surfaces. Reinstall. Same with whatever connection your battery ground cable has. And, there should be a secondary ground from the engine to the frame as there always was on a new car from the factory. Is it there?

[Deleted User]

wano1949 ,
You asked about why 6-volt cables are bigger than 12-volt . Thinking I suppose higher voltage = bigger wire.
As Geoff stated Ohms law governs these circuits. Wattage is the power rating given to most things like lamps ,motors etc. It takes a certain number of watts to do a certain amount of work or make a certain amount of heat.
You can find out the wattage in a circuit by multiplying the amperage X the voltage.
12 volts X 10 amps = 120 watt
6 volts X 20 amps = 120 watt
Both of these have 120 watt loads operating yet one circuit is running 20 amps thru the wires and the other is running only 10 amps.
This is why the 6-volt system needs bigger wires to do the same thing. It takes a given number of watts to spin over the Hudson engine . And that number more or less is the same if its a 6-volt system or a 12-volt system.
Hope this helps,
Roger

ESSX28-1

I've made cables for my 6 volt system from old welding cables. These carry the current to the starter motor easily as they are originally designed with very high current carrying capacity.

[Deleted User]

Very true ,welding supply company is a good source for cable and end connectors,
Roger

Roger Harmon

There is a braided ground strap from the motor mount to the battery tray in addition to the able to the battery. Largest voltage drop is .3, smallest is .09. Total is .75 volts. Too much! I can get bulk cable at my NAPA. I used 1/0 for my Model A last fall, with good results. Can I use 1/0 on the Hornet or should I go to 0/0?

[Deleted User]

1/0 should be ok . If you solder your cable ends on be sure to use a rosin type solder not an acid based type. The acid type is not for electrical and will cause corroded connections later on,
Roger

RonS

Roger, call either Y&Z or Rhode Is Wiring. Have the length and color(black) and the terminal post (either Neg or Pos) info ready. They will make them to order in REAL 00 with soldered terminals. I used 00 for the battery to motor mount as well as to starter switch. This avoided the floppying around of the braided cable. Do not use a green wheel battery kill switch. They block the current necessary on a six volt system. PS the cables that the Model A venders sell is 3/8 #2. I just 2 months ago installed a shut off on my 31 Tudor. Parts from Brattons. They advertise #1... it's not. the terminal has 3/8 2 stamped on copper end.

jjbubaboy

Hey Roger,
I too made my own. Got one of the cables locally and got the rest of the parts, red cable and large heat shrink tubing to cover the very end I believe from Del City. Got good terminals and 'solder lugs' that go in the terminals and flux. Flux, drop in the lug, then you heat em with a small propane torch just enought to melt the lug, push the cable in and "voila". Worked great and looks very neat.
Jeff

Jon B

Tractor Supply (if you have those in your area) has 6 volt cables (there are a lot of pre-12 volt tractors still out there). As to whether the gauge is correct, I do not know.

One good source inside the Club is Dave Kostansek, who has them made up at the different lengths needed for various-year Hudsons.

As to the "green knob" switches, I was told the same thing (they're too light gauge for 6 volt) by a Hudsonite who knows those things. However, I did a quick modification of one, prying it apart into two pieces. One segment is bolted to the negative terminal of the battery, the other to the cable that runs to the starter. The two plates that contact one another have a large surface area for conducting the amperage. The "green knob" now only mechanically holds the two sections together. The advantage of doing this, rather than tightening and untightening the cable clamp from the battery post, is that you don't need a wrench, plus there is no wear on the battery post from the clamp continually being tightened and untightened.

Roger Harmon

I got the 1/0 cable, ends and battery connections at NAPA. I cut, crimped, soldered and heat shrank the cables together, shined the terminals and assembled: Now it turns over faster than a politician! Thanks everyone for your help.

[Deleted User]

That's good to hear ................
Roger