Help! Wiring in a kill switch..

S

Silkworm

New member
My head is spinning, I'm not good at electronics or wiring, so please help me figure out what I need to do here. Reference this graphic that I found.
http://www.ssdiv.com/killsw.gif

Ok, so the battery wire goes to one of the two big poles. A wire then goes from the other big pole down to the starter. That far I understand.

Now, based on this pic, and other descriptions, It looks to me that I'm supposed to also wire the alternator output wire to one of the two big poles. But which one? The one running from the battery? or the one running to the starter?

Ok, I'm also supposed to run a wire from the starter side of the big pole to one side of terminal 1 (normally closed). The other side of terminal 1 goes to the supplied resistor, and then to a ground. Correct?

Now, terminal 2, is supposed to go inbetween the ignition switch and the coil. However, we have multiple coils in the 2nd gen RX-7. so which wire do I splice this into? Sorry, not good at reading wiring diagrams.

Thanks for any help you guys can offer. THis is for a 2nd generation RX-7.

PaulC
 
Not real familiar with 2nd gens, nor with the switch you have. I must admit that the wire with the resisor going to ground has me baffled.

Anyway, heres what I did with my Moroso switch. Basically, place the switch to interupt the main battery + cable. Lets call from batt to switch terminal A and from switch to the rest of the car terminal B. Attach alt feed/power wire to terminal B and you should be pretty much set.
 
Geo46,

Now I'm confused. If you connect the Battery pos to "A" and the Alt wire to "B", when you open the switch the Alt wire is still providing voltage to the motor (fuel pump).

As to the dual coil setup, At some point the hot wire to each coil will terminate at a common point. Wire to that point or common wire and power to both coils will be cut at the same time.

Is the resistor to ground there to protect the diodes in the charging system?
 
http://users.tellurian.net/hughes/articles/master.html

This describes why you shouldn't use a 2 pole swtich like Geo describes. Dunno how accurate it is, but that's why I went with a 6 pole.

The resistor is to protect the alternator.

Like I said, I'm horrible with wiring diagrams, so I was hoping for some easy help, tell me which wire if you know.

Otherwise I'll spend the next 2 weeks trying to figure this out...

PaulC


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Find the wire that runs from the battery to the fuse box under the hood. Splice a two pole kill switch into it. Simple and effective. K.I.S.S.

Chris
 
If your alternator is connected to the opposite pole of the switch than the battery everything on the ALT pole of a 2-pole switch will remain hot when the switch is open. Two pole switch(on the FF) is fine when the only power source is the battery.
 
sorry Paul to add to confusion but, I have a Moroso 4 pole switch and am having charging problems as well. I have two large poles and two small ploes on my switch,

2 large are positive batt in and batt to fuse/starter out.

2 small are fat alt wire in and out.

I followed the dam directions that came with switch but alt gauge has never showed it charging even after buying new alt.
 
BS. You can do it all with a simple two pole switch. It's how my last two cars have been done. Car running, turn the swirch off, and it stops. Altenater still worked/works on both cars. Like C. Ludwig said, K.I.S.S.!
 
George,
With the 2-pole switch wired in series with the BAT+:

How is the car going to "die" when the switch is openned? The alternator is still supplying voltage to the ignition circuit, and fuel pump.

You must connect the ALT and the BAT+ cable to the same side of the switch

If you have only inserted the 2 pole switch in series to the positive cable and it dies your alternator is not supplying enough voltage for the ignition system at whatever rpm the motor is turning when you openned the switch. If it works at idle, will it kill the motor at 5000rpm?
 
Quickshoe, please reread my first posting on this subject.

Doh! My bad. After re-reading my own post I see that I did write it bassackwards.
Alt wire should indeed go to the Batt side if the switch.

Apologies

[This message has been edited by GEO46 (edited September 19, 2002).]
 
Exactly, the hot wire off the alternator goes directly to the + battery post. Then wire the two pole switch in series with the hot lead from the battery to the power feed of the junction box. Pull power off the switched side of the master switch for you fuel pumps. Even if the ignition remains on (which it can't) cutting the fuel kills the motor.


Chris

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Chris Ludwig
08 ITS RX7 CenDiv
 
OK, how simple can this be. I have the battery on the floor where the passenger seat was. The positive line that goes from the battery has a switch mounted outside between the hood and the windshield on the drivers side, in between the battery and everything else. When you turn off the switch, NOTHING gets any power, as the positive is simply disconnected. When you turn on the switch, everything has power.

The simple effect is just disconnecting the battery.

When I first had the car it didn't have the switch, and I had a reputable race car supply and manufacturing company install it.

------------------
G. Brooke Carter
# 10 Challenge Car
Calgary, Alberta
 
That's what I'm saying.
wink.gif


Chris

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Chris Ludwig
08 ITS RX7 CenDiv
 
This is simple 1st symester DC electronics.

Kirk, are you out there? I'm a lousy teacher.

Originally posted by bcarter:
OK, how simple can this be. I have the battery on the floor where the passenger seat was. The positive line that goes from the battery has a switch mounted outside between the hood and the windshield on the drivers side, in between the battery and everything else. When you turn off the switch, NOTHING gets any power, as the positive is simply disconnected. When you turn on the switch, everything has power.

The simple effect is just disconnecting the battery.
Click to expand...

Bcarter,

I am with you to this point. Everything you said is true.

However, if this is indeed the way your switch is installed it will not kill a running motor with a working alternator.

It will prevent a non-running motor from starting and cranking, but will not kill a running motor.

The reputable shop may have a ton more racing knowledge and fab skills than I ever will. But, if this is the way your switch is wired they are lacking in the whole concept as to why that switch is there!

Go try it on your car. If it kills the motor take a closer look as to where your ALT wire is going.



[This message has been edited by Quickshoe (edited September 19, 2002).]
 
Well, I'll look, as it does stop when I turn off the switch, as I do when working on the running engine. Now, I also have very little wiring in the car, ie: alternator and distributor, nothing else except back lights, and some dash stuff. I'm doing final check for the weekend tomorrow, and I'll post Monday after the races.
 
One more time. Running the hot alternator wire directly to the + lug on the battery and then drawing current off that lug will isolate the alternator and kill the motor when the master switch is open. Would bet that is the way BCARTER's is wired.

Chris

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Chris Ludwig
08 ITS RX7 CenDiv
 
This is the simpelest method for a 2nd generation Mazda.(It's also one of the cheapest)

Use a 4 pole switch.

Positive from battery to one side of switch and then from the other side of the switch to the starter. (Big poles of the switch)

The smaller wire that goes from the positive terminal of the battery dirrectly to the fuse block on the drivers side fender needs to be disconnected and extended to attach to the starter side of the switch. This is the wire that supplies power to those tail lights and and interior lights. You need to do this because you will get caught in tech for having power with the switch off.(use same guage of wire)

Locate the white wire with the red stripe that connects to your ignition switch, this is the main ignition power wire. Just cut it and attach the ends to the 2 small poles of the switch. When you turn off the emergency switch it acts like your turning off the key, you don't have to rewire or touch the alternator. 5 years this way and never had to change an alternator. This method brakes the ignition systems connection to power, it dosen't matter if the alternator is spinning because the power is not getting to the ignition.

I welded a tab to my roll cage near the drivers side mirror. I can get to it and so can a track worker in an emergency.

[This message has been edited by Karl Bocchieri (edited September 21, 2002).]
 
Originally posted by C. Ludwig:
One more time. Running the hot alternator wire directly to the + lug on the battery and then drawing current off that lug will isolate the alternator and kill the motor when the master switch is open. Would bet that is the way BCARTER's is wired.

Chris
Click to expand...

I've heard of cars wired this way failing tech because then the kill switch does NOT cut all electrical circuits as required (the wire to the alt is still hot). The tech inspectors will not only see if the switch kills the engine (it will) but then take a voltmeter and measure the output post on the alternator with the engine off and the kill switch off. If it reads 12V (battery voltage), you fail.

MC
#14 GP VW Scirocco
 
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