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Battery and Alternator Cutoff Switch

Flash

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Hey have a 72 Charger with 318. Looking to install a cutoff switch for a few reasons (parasitic drain, theft, fire/safety). I want to install one in the cab of vehicle where I could reach it easily. Not looking for one that can used from outside of the vehicle.

Has anyone installed one and what did you use?
 
I use the Moroso switch.
Me too. Ive got two, one nhra required on the rear valence, another about 90% concealed behind and under the passenger seat. If they arent both on, it aint goin nowhere! (Very small car, easily reachable from driver seat).
 
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You could use a switched solenoid to kill the battery. At that level only one small positive circuit interrupted by the manual switch of your choice.
Mike
 
You don't actually need to cut the alternator hot wire but simply the ign system along with the batt of course. That will cut the alternator feed too. I think that's easier to wire than cut both, batt and alt hot wire.

These use two big studs for batt wiring and two small terminals for ign wiring.
 
So the Moroso 74101 instructions show connecting the battery and alternator to the same side of the switch. So I'm guessing that would work in cutting off power to both?

493 Mike - what would you suggest, just searching the internet I noticed Painless has a remote solenoid disconnect. Would something like Painless 30204 work to cutoff both battery and alternator?

Nacho-RT74 - what setup could I use for what you suggest? So I would wire the battery hot to disconnect, what would I need to wire from the ignition circuit to disconnect?

So if these are dumb questions! I'm just starting to learn automotive wiring etc.
 
They cut the battery power, but as soon you also cut de ignition circuit ( blue wire coming out from ign switch ) you don't need to cut the alternator hot wire anymore because alternator will stop sourcing (alt field is sourced by the ign network). There are several brands. Dunno which on is the best but normally the ones I meant look like this:

ion-battery-and-alternator-kill-switch-combination-battery-and-alternator-kill-switch-add-image1.jpg



or this:

FIA_approved-battery_isolator_switch-with-removable_key_for%20cars_1.jpg


and they are wired like this:

020_011.jpg
 
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If your going for anti theft didn’t someone make a hydraulic keyed valve for your brake system? Between a no start and locked brakes the only other anti theft I can think of is a removable steering wheel and an owner with a 1187 and plenty of rounds for it.! Otherwise a stolen wrecker will get it as I’ve seen that happen in Caseyville Il.
 
I worked with a fella 40 odd years ago that had a brother in the used auto parts business. He had a penchant for "finding" empty/abandoned vehicles along the highways and just snagged them with his wrecker and headed to the yard. I don't remember hearing about him ever getting caught.
Mike
 
So the Moroso 74101 instructions show connecting the battery and alternator to the same side of the switch. So I'm guessing that would work in cutting off power to both?

493 Mike - what would you suggest, just searching the internet I noticed Painless has a remote solenoid disconnect. Would something like Painless 30204 work to cutoff both battery and alternator?
Try this:https://www.jegs.com/i/Ron+Francis+Wiring/788/MS-56/10002/-1 for a manual switch. I know there are solenoid like the 30204 that also cut the alternator output but, I looked enough. Your turn! If the alternator is not cut your not safe.
Mike


Nacho-RT74 - what setup could I use for what you suggest? So I would wire the battery hot to disconnect, what would I need to wire from the ignition circuit to disconnect?

So if these are dumb questions! I'm just starting to learn automotive wiring etc.
 
F4R/T - theft could be part of it, but mainly looking to prevent any parasitic drain and to cut everything off in case of a fire.
 
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