Hello all I want to hook up a disconnect switch on My 1954 chevy 3100 12 volt system. Should I use the positive or negitive wire comming from battery any neat locations to put a switch any ideal's thought's tip's ??? thank you in advance!!!!
Most of the time on the fleet, we have them on the negative cable. On my '49, I had it on the passenger inner fender, I believe. You had to reach for it a little to operate it. I've never believed in making anything easy for a thief.
Be sure to get the heavy duty disconnect from a racing supply place like JEGS or Circle Track, not the flimsy 100 amp switch most of the online stores sell. You'll need one with at least 500 amps capacity, and if a 1000 amp switch is available, get that one. It really doesn't matter which circuit gets broken, positive or negative. Some of them are available with a bell crank and a remote handle so the operating linkage can be hidden under the dash with the doors locked for extra security. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Isn't the standard transmission good enough to thwart most thieves? "What is that third pedal for?" I saw where someone installed a switch thru the front of the seat riser above the battery. Negative cable is probably the safest, as you don't have to worry about something rattling around and contacting a hot terminal. Marine Battery disconnect switches (Marinco brand for instance) are readily available. Here is one rated 400A Continuous / 600A 5 mins Intermittent / 1500A 10 secs Cranking. Most of them can be flush or surface mounted.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
I put one in last year on my ‘52 3100. I may have been the one that klhansen is talking about. I installed it on the passenger side seat riser as I wanted it within reach when I was driving. I installed it on the negative side to keep the cables as short as possible and to keep the positive cable (12 volts and several hundred amps) from passing thru the floor pan. If the ground cable shorted out, the worst that could happen is it completes the circuit needed to run the truck.
I bought the switch and the cables from eBay. I listened to Jerry and bought a switch with a 195 amp continuous and a 1,000 amp surge. Search for “heavy duty battery disconnect switch” and you will find many to choose from.
The cables can be ordered at whatever length you need. Search for “battery cable negative 2 gauge” and you can choose the cable ends and length.
I installed one end on the battery and the order to the frame where the original cable was attached.
If you decide to install the switch in the truck, make sure you install grommets where the cables pass thru the floor. You can buy them at your local hardware store.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
If you happen to have a sound system with a memory for preset radio stations, a clock, or other functions that require a "keep alive" circuit, you'll need to put the heavy current switch on the hot side of the battery and run a dedicated low-current fused circuit that supplies constant voltage to the items that don't need to have their power interrupted. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
If you happen to have a sound system with a memory for preset radio stations, a clock, or other functions that require a "keep alive" circuit, you'll need to put the heavy current switch on the hot side of the battery and run a dedicated low-current fused circuit that supplies constant voltage to the items that don't need to have their power interrupted. Jerry
Why couldn’t the low amp fuse be bridging the two terminals (on the switch) with the switch on the negative side? Any attempt to start would blow the fuse as well as a direct short. Just asking.
Last edited by Phak1; 01/05/20211:35 AM.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
That might work, but doing something like turning the headlights on, etc. would blow the fuse also. Interrupting the power to the starter and the main fuse block and powering the "keep alive" circuit to the sound system with about a 5 amp fuse wired straight to the battery would be a more logical approach, IMHO. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Makes sense. I wouldn’t put the switch inside then. I would look into remote battery disconnect switch in that case. I don’t have a radio so it didn‘t matter to me.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
If we all buy this one and the extended warranty, maybe Jegs will quit selling a 20A continuous, 125A momentary switch, when we all turn them in for warranty when they burn up. On second thought, don't buy that one. [where's that rolleyes emoticon?]
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
Some of our equipment, to put it nicely, is not in pristine condition so battery drain happens. We use a continuous duty solenoid (relay) with a switched ground. Everything is dead till the switch, keyed or toggle, is flipped and then the battery cable circuit is complete. The heavy duty ones look just like an old Ford starter solenoid. For car/truck use the relay could be mounted anywhere along battery cables and just 14g run to the switch. The hot wire to the relay is the only circuit that stays hot so drain is unlikely.
