switch question

[grudd440]

what amp switch would i want to shut off and on an alternator?  im talking about a toggle switch.

[68_Val_Sedan]

you would need a 60 amp switch.   it would be way easier and cheaper to switch one of the field wires.  it would have the same effect.  you could use any toggle switch, rated for 5 amps or more, for the field wire the current will be less than 5 amps even at full charge

[west]

why do you want a switch?

[grudd440]

to shut on and off the alternater. the switch idea wont work. i had a plan. my engine  isnt shutting of when the master switch gets turned off. I was going the buy the painless relay, but i'm now thinking i made a wiring mistake.

I have a 1 wire alternater. Im running my ignition wire off of the hot terminal of the alternater. what if i ran the wire from the battery to the switch, rather than from the alternater? im not the best at wiring.

[Jim_Lusk]

If the engine isn't shutting off with the master switch, then your ignition is always connected to power. You need to switch the ignition and fuel pump (if electric).

[grudd440]

let me just clarify that the engine will turn on an off with the ignition switch, but wont turn off when the master switch outside of the car is turned off.
if the master switch is in the off position, there is no power at all to the car. but once the car is running the master switch wont shut the car off. but i can turn the car off inside of the car with the ignition switch. 

[west]

put the ALT wire on the + batt. side of the switch and the ign.(starter) wire on the other side of the switch

[grudd440]

that sounds like it would work. I already have the alternator wire ran back. ok. sounds good to me.

[grudd440]

i also just realized there is a very similar topic also going on.

[grudd440]

i tried this and it still wont shut the engine off, last resort must be the painless wiring relay.

[cu440da]

That doesn't work because the alternator field needs to have its path broken or you get feedback and it wont shut down. I just went through the same thing you are doing. I upgraded to a 4 post switch, although I'm not sure that was really neccessary. Wired the batt cable like normal and ran the alt output back to the switch and then back up front. This will kill the car when the switch it used.

[grudd440]

my painless relay came today from summit so i will see  what happens.

[PureGTS]

  What I did was use a relay, from a camper/trailer supply store, on the alternator's out put wire and a switch to turn it on and off. The relay is designed to use minimal power to turn it on so, unlike the Ford starter relay it looks like, it is happy to do its job for extended periods of time without melting down. The relay is used in campers and trailers for a charging the battery on board the camper or trailer while you are going down the highway. The 4 wire battery shutoff switch you're getting can be used to control that relay or a manual switch can be installed. Just with the manual switch you'll need to remember to arm and disarm it in the staging lanes before going to the line.