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My kids like to play in my '46 1/2 ton.. The way it is wired now though the starter is hot all the time. if you step on the starter it turns over, even with no key.. I found a 200A relay at:
http://www.wiringproducts.com/index1.html
I'm thinking I'll fuse a wire to the ignition and let the ignition connect the battery.
Anybody ever actually done this?

I've not done it, but I don't see why it wouldn't work.
A simple battery shutoff switch would be cheaper, though.

regards,
Leon

4D6,

I haven't done this but I have a few thoughts on it. A 6 volt starter can pull 200 amps when it's really working hard. The other concern would be that the relay, if it's electrically held in, would have to have a duty cycle that allows you to drive for extended periods of time with it energized.

Your method of energizing the relay would have to be wired directly from the battery or the battery side of the relay for it to operate, it would be powered all the time.

Have you thought about one of those twist type battery disconnect switches mounted somewhere convenient?

I think this has been discussed here before and the problem was finding a solenoid (relay) that could handle being energized for hours at a time, as you drove around. Most were made for momentary service. There were some for maintained service (I think) but they were quite expensive. Good luck.

Stuart

Yeah, I like the battery disconnect better than a relay too. It also protects against little curious hands pulling on your light switch and running the battery down, or honking the horn to death.

The relay wouldn't have to power the whole truck, just the starter. You would move the system feed wire from the starter to the battery side of the relay. That way the relay only controls power for the starter.
That said, I am also a proponent of the battery shutoff switch.

regards,
Leon

Leon,

On a AD truck or a Deco truck, that connection on the starter switch that the BATT connects to IS power for the entire truck. Did I misunderstand your post?

That is a great idea. The rest of the system is switched by the ignition so why waste relay on other stuff.. I plan to give it a try, I'll ley y'all know how it goes in a few hundred starts..

atomarc,

you're right, my bad.

The way I was thinking would require another switch to control the relay so that it could be turned on when the starter was needed, and then turned off to keep the relay coil from overheating. I didn't think it through hard enough.

You could probably use a lever-type brake light switch actuated by the starter linkage to operate the relay.

Or, I wonder if the R-200A relay is actually rated for continuous duty? That's the concern that started all this.
Their #67015 is, but it only handles 85 amps.

regards,
Leon

Just use a 6-volt Ford starter relay, and wire the energize lead to a hidden push button under the dash. When you push the button, the relay closes and puts battery power to the top terminal on the stomp starter switch. Those old relays were used through the 40's and 50's until 1955. There's one small terminal that is grounded by the starter button on the older ones. Newer models needed battery voltage from the "start" position of the ignition switch.

Jerry

ya just learn something new everyday

http://www.wiringproducts.com/index1.html
Battery Terminal Solder Slugs
Battery terminal solder slugs were developed as a fast method for attaching a battery lug to a cable. A cost-efficient method that eliminates the need for and expensive crimping tool. Creates a rugged sealed connection for optimum performance. Slugs are color-coded for gauge size to industry standards. Select sizes from the drop down box.

How to use:

Strip cable so that the exposed copper reaches the battery terminal bottom
Apply several drops of flux to the exposed copper of the cable
Place the proper slug size into the battery terminal, and secure the battery terminal in a vice
Heat the base of the battery terminal with the slug inside using a propane torch or similar heat tool. As the battery terminal is heated, apply gentle downward pressure on the cable until the cable is inside the terminal. Remove heat source. Allow time for the connection to cool before handling
Always wear protective eyewear and clothing.

thanks 4D6

The relay shown is a White Rodgers 586. Here is the manufacturers web page and spec sheets

http://www.white-rodgers.com/wrdhom/common/ptech/relays/relay_06.htm

http://www.white-rodgers.com/wrdhom/pdfs/sell_sheets/R-4005web.pdf

However I would NOT use it as a battery contactor as it will ultimately fail due to the high in-rush current of a starter will eventually carbon arc the contacts. A battery disconnect would be a better choice for the application described. You could always use two or more, however that would be pricey.

On another note, the prices from wiringproducts are too high, even higher than McMaster Carr (scroll to bottom - pn 7995k31 at $45.16). This relay is the most common starter relay for every diesel engine made today. It is the relay used as the pilot for the starter's solenoid. Can be obtained for about $35 at any Diesel Repair facility.

K-I-S-S install a battery interuptor switch $15.00 at any truck stop. $25.00 at your avarage parts store, and $50.00 at a racing parts house.

Change out to a later key switch and a remote starter solenoid.

I remember a cousin and myself driving a small landscraper/tractor machine all around a work site just standing on the foot starter. What Fun! If our father's had gotten the word we would still be grounded or worse.

I have the green knob disconnects on all my stuff.