Pro Mag 44 Kill Switch Relay (pn 8134)

Anyone find that when using this relay, the Mag Kill switch works backwards? In other words, when you kill the mag on the switch panel, it actually puts power to it and vis-versa. I wired it exactly like MSD shows. The tech at MSD says that is the way it was made. Am I missing something?

Any help is appreciated.

Thanks,

Fred

 

Thanks Mike. Do you guys just live with the switch being that way or can you reverse something? Do I just need to get use to pulling the switch to kill the mag? Thanks again for your quick response. I can go have a beer and relax now.

Fred

 

Thats how it works. I threw the thing out. Works great now!

 

Thoes solonids when energised have closed contacts which completes the ground to the mag. I also had them but took them off. If you are running a six shooter or retard box you can just use a good quality single pole switch to furnish the 12 volts to the retard box which will turn the mag on to run.
turning the switch off takes the 12 volts off the retard and the motor will not run. I have been useing this setup for three years. had the battery wire break on a run at about 500 feet which is the same as turning the switch off.
The driver almost hit his head on the steering wheel it was n instant dead motor.
Many of the top fuel guys are doing this same thing but I know there are folks out there that have used the old Mallary and other expensive switches for years and they will probably continue doing so.

 

Just to make sure..... I have a Auto-Rod Controls control panel and I am using the ignition switch from that panel to control the Mag. When I turn that ignition ON, the relay kills the Mag. When I turn the ignition switch OFF it turns the Mag on??? Mike the aircraft switch that you described works properly since when you close the red cover it kills the motor. Mine does the opposite. Is it possibly in the switch? Sorry but I have to figure this out.

Thanks again,

Fred

 

I didn't wire mine like the MSD drawing shows, I run power thru the old school "big red button" on the dash , back to the 8134 relay and the negative side goes to ground ,this way when the big red button is out the mag is on then you just slam it to kill it fast and it works great!
I think my way is safer if the switched hot lead gets shorted out the mag is dead, where as with the switched side going to ground if the switched side gets shorted the mag is still powered.
I don't know why MSD shows to put the switch on the negative side, but I called them when I wired my car and they didn't give me a reason for wiring it that way but they said my way was acceptable .

 

Thanks to all you for the info and explaining how the darn thing works. This is a great site with some really cool people.

Fred

 

We run our setup the same way Mike does. With the aircraft switch guard, it's tough to lift the guard and get at the switch with the driver gloves on, as opposed to just slapping the switch guard down and shutting the car off. So far, haven't had a problem with the car shutting itself down during shake, but I'm sure it's probable.