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Discussion Starter #1
I have done a search on the forum and found many post on push button starter switches but most of the info seems to address more complicated systems than mine.

I am working with a 1975, CJ5, Jeep. This Jeep is an old school in line 6cyl. No smog at all and of course no computer. It is really basic.

My question is can I splice a proper size toggle or rocker switch into the hot feed to the ignition? I would do this so I could mount it hidden but accessible as anti theft measure.

I ask this because I was thinking of adding a push button starter switch that has it's own switch and may be easy to wire any accessories into if needed. I don't think any accessories are wired directly into my ignition switch as is. I am away from the jeep at the moment so I haven't studied the wiring on the current (probably stock) ignition.

The links below show a couple examples of what I have been looking at. Before buying anything I would hunt around to see if I could get something of higher quality as reviews seem to suggest these examples might be china junk.


or


Please let me know if I'm missing something...........thanks
 

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1949 Ford Coupe RESURRECTION
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Just about any auto parts store will have pushbutton and toggle switches. Probably made in China too, but you may have no choice in the matter... toggle switch should feed accessories which includes ignition and one side of the push button switch. Push button switch feeds solenoid on the starter.
 

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Old(s) Fart
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The ignition doesn't care it the switch is a toggle, key switch, or just two wires twisted together. Electrically they are identical. The only issue is to be sure the switch is rated as sufficient amperage. I guarantee that there are loads besides the ignition that go through the switch - any accessory that only works with the key on is powered from the ignition switch. That's typically wipers, heater fan, gauges at a minimum.
 

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Discussion Starter #4
That is what I thought. Does anyone know how many amps the average starter draws? I will look one for this jeep up and see if the specs tells me.
 

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Discussion Starter #5
I feel like I must be missing something here. I looked up "heavy duty" toggle switches on line and the largest I see is 50 amp. I also looked up what the average 12 volt starter draws when cranking and see 150 to 200 amps needed. It is hard to believe the amps going through my basic/cheap ignition when cranking is more than a heavy duty switch will handle.

Could it be the toggle would be fine because the path to the starter from the ignition is going through a relay? Are the amps bumped up at the relay?
 

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Super Moderator
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You need to use the toggle switch or whatever to power a solenoid. That supplies the starter with the big amperage that it needs.

 

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Old(s) Fart
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I feel like I must be missing something here. I looked up "heavy duty" toggle switches on line and the largest I see is 50 amp. I also looked up what the average 12 volt starter draws when cranking and see 150 to 200 amps needed. It is hard to believe the amps going through my basic/cheap ignition when cranking is more than a heavy duty switch will handle.

Could it be the toggle would be fine because the path to the starter from the ignition is going through a relay? Are the amps bumped up at the relay?
The ignition switch doesn't carry the full current to the starter, it only carries the current needed to activate the solenoid. That's probably under 20 amps.
 

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Another option for anti theft is to use a relay to power the ignition and/or starter and have it activated by another accessory. For example , use the brake pedal switch to activate a relay in the wire to the starter solenoid. If you step on the pedal and hold it down the key works fine and the starter turns. If you don’t step on the brake it won’t start. You can use a similar scheme with a hidden push button, or the park light circuit, or a switch for off-road lights. The point is that you have to do two things to start the Jeep, not just turn the key.

You could also use an electric fuel pump and a hidden power switch. The switch has to be on to keep the Jeep running. A carbureted vehicle will start using the fuel in the float bowl, but die out a block away since there is no fuel pump running. Most thieves abandon a vehicle that just stops on the road and won’t start.

Bruce
 

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Member - AMC/Rambler "guru"
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I use a relay powered by the key switch to activate a relay that powers a small six circuit fuse panel for all my accessories that I want on a switched circuit. Saves the switch by reducing power through it.
 

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Old(s) Fart
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I use a relay powered by the key switch to activate a relay that powers a small six circuit fuse panel for all my accessories that I want on a switched circuit. Saves the switch by reducing power through it.
You use a switch to operate a relay to operate a relay? Why?

Look, if the current in the circuit is less than the rating of the switch, all this does is increase complexity and possible failure modes. The only other consideration is length of wire and voltage drop. I think a lot of people misuse relays thinking they are "protecting" the switch, when in fact they are just adding wiring and problems. I've had far more electrical problems at connections that at switches. To bring this back to the OP's question, the starter solenoid IS a relay already. The whole point of that design is to reduce current through the ignition switch. Adding another relay in series doesn't make it more reliable.
 

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Member - AMC/Rambler "guru"
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Good point. I'm not using the relay for the starter, nor suggesting that -- the starter relay/solenoid in my car is on it's original circuit (I'm using a Jeep 4.0L that has a starter relay). I'm using the relay to power a separate fuse box so I don't have four things that I want to be off with the switch directly on the switch (six position fuse box). I don't think that anything on the fuse box is relay powered, but it might be. In my case it's a 1963 ignition switch that is unique to only 65-66 Ramblers and would be hard to replace though. So anything to save wear and tear on it is a plus.

While adding a relay adds some complexity to the wiring, it can also make things easier. In my case it moves accessory power taps to a common, easily accessible point. All I need to do is push in an appropriate size fuse and connect a female spade connector to a wire and be ready to go. Running a relay for all switch items, even the starter solenoid/relay in some case might be beneficial. Run smaller wire from the switch to the relay, which then trips a higher powered circuit. maybe with multiple taps. The start circuit usually has nothing BUT the starter relay or solenoid on it though, and the solenoid/relay doesn't draw much power, so no real point in using a relay there. Only in the accessory and RUN circuit would there be much benefit in relay activation. The RUN circuit is usually engaged in the switches START position as well as RUN position.
 
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