Master Disconnect Switch

Typically your starter has 2 power wires run to it... 1 is the main power wire from the battery (0-4 ga), the second is the switch power, that activates the starter solenoid... the solenoid works like a big relay....

So really if you are wanting a remote kill switch to cut the vehicle off during a rollover, you dont need to worry about the starter wire; just put a kill on the fuel and ignition systems, which can be through a relay to allow a lower amp switch
 
paradisePWoffrd said:
Typically your starter has 2 power wires run to it... 1 is the main power wire from the battery (0-4 ga), the second is the switch power, that activates the starter solenoid... the solenoid works like a big relay....
So really if you are wanting a remote kill switch to cut the vehicle off during a rollover, you dont need to worry about the starter wire; just put a kill on the fuel and ignition systems, which can be through a relay to allow a lower amp switch
Click to expand...
Ben,
I agree thats why I was just wanting to use a relay for the ignition circuits. I have a 2/0 welding cable from my bat to the Mamouth starter. I am not worried about the starter doing anything, just want to isolate than big-ass live cable connected to my bat.
 
well I am assuming that your 2/0 cable is running only to the starter, and you have seperate cables running off for everything else... If not I would possibly do this... Also if you put a main cutoff in the ground wire from the battery to the frame/motor, it will take care of the starter too...

if you are wanting to mount a hidden starter disconnect switch, you could use a Ford type solenoid in the starter power wire, but with it, as most big solenoids/relays to handle that kinda power, will have open post-type terminals, that can easily be jumped across to turn the starter...
 
paradisePWoffrd said:
well I am assuming that your 2/0 cable is running only to the starter, and you have seperate cables running off for everything else... If not I would possibly do this... Also if you put a main cutoff in the ground wire from the battery to the frame/motor, it will take care of the starter too...
if you are wanting to mount a hidden starter disconnect switch, you could use a Ford type solenoid in the starter power wire, but with it, as most big solenoids/relays to handle that kinda power, will have open post-type terminals, that can easily be jumped across to turn the starter...
Click to expand...
Ben,
Yes, the 2/0 only goes to the starter. You have some good points on the solenoid. At least it would be one more step to foil would be thieves. I am sure a professional could steel anything, but at least it would keep the ammetures away.
 
etjeep said:
Dawson,
Thanks. I can't think of any RV places over there right now. I will keep my eyes open though. I was not even thinking of doing this two weeks ago. I'm going to call it progress.
Click to expand...

Collage Park RV, and they are going/ have gone out of business.

There are 2 more RV places on Highway 70 toward Clayton, Hawleys (just outside Garner) and Camptown or something like that across from Wal-Mart in Clayton.

As for isolating the ground, that will be tough, you whole truck is chissis ground, meaning you potentially have several DOZEN ground points through out the vehicle. anyone of which can and will back feed at an inopportune time causing you much issue.

You really want to rewire the whole truck and isolate all lights and accesories from the chassis, including dash gauges , and even isolate the winch from the frame (potential backfeed source)
 
etjeep said:
Ben,
Yes, the 2/0 only goes to the starter. You have some good points on the solenoid. At least it would be one more step to foil would be thieves. I am sure a professional could steel anything, but at least it would keep the ammetures away.
Click to expand...
Ben,
After thinking about it some more tonight, I may just blow off the starter cable like you suggested and secure it. I gotta simplify this....at least for now.....just go with a relay.
 
Blkvoodoo said:
Collage Park RV, and they are going/ have gone out of business.
There are 2 more RV places on Highway 70 toward Clayton, Hawleys (just outside Garner) and Camptown or something like that across from Wal-Mart in Clayton.
As for isolating the ground, that will be tough, you whole truck is chissis ground, meaning you potentially have several DOZEN ground points through out the vehicle. anyone of which can and will back feed at an inopportune time causing you much issue.
You really want to rewire the whole truck and isolate all lights and accesories from the chassis, including dash gauges , and even isolate the winch from the frame (potential backfeed source)
Click to expand...

Kevin,
Thanks. I was thinking I could isolate the motor and body grounds with the switch. Would that work? Hell I don't want to rewire the whole jeep.
 
Typically your negative battery cable runs from the terminal to the frame & motor, then all your things are grounded to the frame/motor completing the circuit.... SO, if you put your main disconnect switch on the ground lead coming from the battery, then it shouldnt matter where anything was grounded down to the frame. As long as it couldnt get back to the negative post on the battery, the circuit is broken....

also if you flip the kill switch on the ignition/fuel when you get out of your jeep, as well as the main disconnect, it really wont matter if the starter works or not, cuz itll never run....
 
Isolating the engine/body isn't as easy as it sounds, yeah, it may be sitting on rubber blocks, but there are bolts thru those, and usually some sort of metal to metal contact some where.

I would wire the hot side so that ONE SWITCH shuts off the whole thing.

an enclosed switch (sealed if you really feel the need) would be good for spark protection

I don't know how the main power is distributed to your truck, there may be several (redundant) positive wires ( like old GM ) all of which would need to be traced and switched.

I'm gonna have a lot of time over the next week or two, If you like I could maybe help you figure out what you have, maybe figure out a way to clean things up ( I've found many redundant/doubled up harness issues on my GMC, I'd bet AMC did similar.
 
paradisePWoffrd said:
Typically your negative battery cable runs from the terminal to the frame & motor, then all your things are grounded to the frame/motor completing the circuit.... SO, if you put your main disconnect switch on the ground lead coming from the battery, then it shouldnt matter where anything was grounded down to the frame. As long as it couldnt get back to the negative post on the battery, the circuit is broken....
also if you flip the kill switch on the ignition/fuel when you get out of your jeep, as well as the main disconnect, it really wont matter if the starter works or not, cuz itll never run....
Click to expand...


Try that in an older vehicle, ( hell even new ones) disconnect the battery while the engine is running, if the alternator is working, and is able to keep up with the load without the battery, it'll still run. it may not be happy about it, but it'll run till something actually removes the power source.
 
Blkvoodoo said:
Try that in an older vehicle, ( hell even new ones) disconnect the battery while the engine is running, if the alternator is working, and is able to keep up with the load without the battery, it'll still run. it may not be happy about it, but it'll run till something actually removes the power source.
Click to expand...

yeah but isnt that because since the alternator is generating the power for the system, it works like a closed loop....

but on the same vehicle, if you take the negative terminal loose from the battery, while it is off... you shouldnt be able to crank it or get energy to anything... which is what i think he wants the main disconnect switch for, not ness for a kill switch
 
paradisePWoffrd said:
yeah but isnt that because since the alternator is generating the power for the system, it works like a closed loop....

but on the same vehicle, if you take the negative terminal loose from the battery, while it is off... you shouldnt be able to crank it or get energy to anything... which is what i think he wants the main disconnect switch for, not ness for a kill switch
Click to expand...


I believe the idea is to acheive both, a kill and a disconnect.
 
Blkvoodoo said:
Collage Park RV, and they are going/ have gone out of business.
There are 2 more RV places on Highway 70 toward Clayton, Hawleys (just outside Garner) and Camptown or something like that across from Wal-Mart in Clayton.
As for isolating the ground, that will be tough, you whole truck is chissis ground, meaning you potentially have several DOZEN ground points through out the vehicle. anyone of which can and will back feed at an inopportune time causing you much issue.
You really want to rewire the whole truck and isolate all lights and accesories from the chassis, including dash gauges , and even isolate the winch from the frame (potential backfeed source)
Click to expand...

Kevin,
Props to you buddy! I went over to College Park RV on New Bern at lunch today. The are going outta business for sure. I was looking for relays, saw they had a bunch of 85 amp continuous duty solenoids (same as a relay just a bigger coil)for $15 ea with their sale price, so I picked up two. So I'll just use one of these for the kill switch and the other for off-road lights or something.
 
paradisePWoffrd said:
Typically your negative battery cable runs from the terminal to the frame & motor, then all your things are grounded to the frame/motor completing the circuit.... SO, if you put your main disconnect switch on the ground lead coming from the battery, then it shouldnt matter where anything was grounded down to the frame. As long as it couldnt get back to the negative post on the battery, the circuit is broken....
also if you flip the kill switch on the ignition/fuel when you get out of your jeep, as well as the main disconnect, it really wont matter if the starter works or not, cuz itll never run....
Click to expand...
Ben,Thats what I was originally thinking. Isolate the frame/motor/boddy ground wires fromt the bat.
 
Blkvoodoo said:
Isolating the engine/body isn't as easy as it sounds, yeah, it may be sitting on rubber blocks, but there are bolts thru those, and usually some sort of metal to metal contact some where.

I would wire the hot side so that ONE SWITCH shuts off the whole thing.

an enclosed switch (sealed if you really feel the need) would be good for spark protection

I don't know how the main power is distributed to your truck, there may be several (redundant) positive wires ( like old GM ) all of which would need to be traced and switched.

I'm gonna have a lot of time over the next week or two, If you like I could maybe help you figure out what you have, maybe figure out a way to clean things up ( I've found many redundant/doubled up harness issues on my GMC, I'd bet AMC did similar.
Click to expand...

Kevin,
Your just gonna have to come over and find out then! My wiring is clean, not like the last time you saw my Jeep. I made a readable full size wiring diagram http://good-times.webshots.com/photo/2221210100069564115esynUy that I am keeping up to date so when I'm done I know what I got. I have one 12V power lead to the old harness, one 12V lead to the fuel injection system and I bypassed the ammeter. I have a winch master cutoff, battery isolator, battery isolation switch and some other stuff to add to my diagram.

I can't do it next week, but I may take a morning or two off the week after. I'll make it worth your while, I'll give you that GM oil cooler pancake and whatever extra fittings for your buggy if you come over and help me with this.
 
paradisePWoffrd said:
yeah but isnt that because since the alternator is generating the power for the system, it works like a closed loop....

but on the same vehicle, if you take the negative terminal loose from the battery, while it is off... you shouldnt be able to crank it or get energy to anything... which is what i think he wants the main disconnect switch for, not ness for a kill switch
Click to expand...

Ben,
Thats right. I plan to use the Cole-Hersee switch when I park the jeep or for engine bay work....thats all. I plan a separate kill switch (maybe a should have used a different terminology but I meant that for the oh sh*t, I'm upside-down). I bought one of those aircraft style toggle switches during lunch as well. Not this one, but similar and cheaper to get me outta the gate at least http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_66526_-1

I also bought a bunch of cheap battery cable and some crimp-on lugs at lunch so I can cut it up and test it out. When it proves out, I'll use those cheap ones for guides and have some nice ones made at batteries plus in Durham. They do a nice job on custom cables.
 
Got several components mounted up on the fender this weekend;
Battery Isolator
Cole Hersey Battery switch
Two 85 Amp continous duty solenoids
one continuous duty winch solenoid switch

Its tight, and is doing nothing for helping the apperance of my wiring. I started to wire it. I think one look at that will be enough theft deterant. I have smaller gauge large wires sourced. Just need to finish up the wiring. Its going to be sweet though.

Another thing that sucked up a lot of time was mounting my winch remote behind the grill. That was a PITA, but is done now.
 
Pretty much finished up the underhood wiring with custom length cables to minimize slack and clutter. Tested out the kill switch and it works like planned. I just need to run the switch wires into the cab and fab up a switch panel.

I hooked all the grounds (block, body, fuel injection harness, winch) to one terminal of the Cole hersee battery isolation switch and the second terminal to the neg bat terminal on one battery. I have the ground from one battery piggybacked into the ground from the other battery.

I am going to take tomorrow AM off and finish up and retest it. I had to take the winch off to get the (short) solenoid pack ground wire attached to the winch ground (It must be a Ramsey thing).

In my initial test, it would not crank...as planned...with the ground circuit (cole Hersee) interrupted. When I had it running, I cut off the ground again and it would not turn off. Its late, so I'll do that test over in the AM...gotta be nice to the neighbors. Remember the cole Hersee is just to isolate the bats when I store the jeep and is not the primary kill. It seems like something was not totally isolated when I cut it off the ground circuit (and its running).

any thoughts?
 
Got the winch wired, grill buttoned up and tests fine.

I tried another test, interrupting the ground connection again with the motor running and it would not shut down the motor. Any thoughts on this? This is not my primary kill switch, primary kill is another relay and it works fine. I don't see a problem with this as a battery isolator, its just bugging me a little. Again the battery isolator switch when off will not let me crank the motor.....this is what I want. I just tried turning it off with the motor on and it did not turn off. Obviously ground is completing the circuit via another route.....I think. Its just bugging me that it only works in one direction as I indicated.
 
after the truck is running, the body is ground, the battery is storage only then, until you need the extra power (blower fans, wipers, radio/amp) unless you have a high amp alt

Is what I was telling you before, you'll pay hell trying to isolate all the grounds to make that a kill circut.
 
Blkvoodoo said:
after the truck is running, the body is ground, the battery is storage only then, until you need the extra power (blower fans, wipers, radio/amp) unless you have a high amp alt

Is what I was telling you before, you'll pay hell trying to isolate all the grounds to make that a kill circut.
Click to expand...

Kevin,
You were on top of that one alright! Actually I do have a high amp (well, 150 amp alt)......so what do you mean unless I have one.

I am happy with the cole hersee switch isolating my bats when not using the jeep.

Here are a few pics, I have my control wiring to route and a little housekeeping etc. ....but I am moving on to the next sub-task.
http://rides.webshots.com/photo/2931295400069564115rZZeIZ
http://rides.webshots.com/photo/2810579830069564115fTdSfX
http://rides.webshots.com/photo/2916215440069564115fleaGk
 
continuous duty solenoid

You can get a continuous duty solenoid from napa also. Have them look up a battery isolator solenoid for around a 1990 model diesel F250-F350. I got mine for around $30.00 It looks just like the starter solenoid from a ford and wires up the same way, but it says on the box and on the part "continuous duty". It is used to isolate the dual batteries on some diesel trucks, not all truck had one, but napa carries the replacement part. I used mine to run winch motor powered air compressor on my 03 F250, until i figured out how to reroute half the plumbing under the hood for engine oba. Just another place to get one if you dont have a RV place nearby.

Tim
 
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