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Rob Liebbe
12-21-2008, 07:27 PM
After moving the battery to the back of the car and adding another cutoff switch in series, the car now runs on if either switch is turned off. I guess it is running on the alternator. I think I know the problem, but don't know how to correct it. I think that I moved the power lead coming from the alternator from the positive post of the battery to the battery side of the starter solenoid and therefore straight to the positive battery cable. Did I eliminate some diode somewhere? Also, both cutoff switches will cut battery power independently if the car is not running.

I hate electrons - you can't see the little fxxxers!!!!

Any help is appreciated. Now where is that wiring diagram Marshall sent out?

Rob Liebbe
12-21-2008, 07:33 PM
Sorry - forgot. There is also a short to ground on the ring connector that leads from the battery side of the starter solenoid to the three fusible links. The wiring diagram shows that at least one of these links goes to the alternator. If the cutoff switches are left on, the battery deep discharges to very dead. Turning off the cutoff switches prevents the drain.

Help.

jeffburch
12-21-2008, 08:27 PM
mine grounds the coil primary thru the supplied hiwatt resistor.

jb

GlennCMC70
12-21-2008, 09:37 PM
just wire your alt output wire to the battery side of the cut off switch that is closest (as in electrically and not distance wise) to the battery.

David Love AI27
12-21-2008, 09:51 PM
Sorry - forgot. There is also a short to ground on the ring connector that leads from the battery side of the starter solenoid to the three fusible links. The wiring diagram shows that at least one of these links goes to the alternator. If the cutoff switches are left on, the battery deep discharges to very dead. Turning off the cutoff switches prevents the drain.

Help.

correct... you need to turn off the master switch... or have a seperate switch for the alt.... the "short to ground" is normally "deactivated" through the ignition switch...

I have the wiring schematics from MM, I will make a copy and run them by the house this week... I can also take a look at the elec for you since I am doing the same at the moment...

Rob Liebbe
12-21-2008, 10:03 PM
Soooo...with the battery in the "rear seat" area and the positive cable from the battery going straight up the main hoop of the roll bar to the first cutoff switch, the alternator output wire needs to be run all the way back to the roll bar hoop? Electrically, this makes sense and is equivalent to the way it was before. But I don't recall seeing this in other cars.

Burch, I see your method would work too, but does it turn off the fuel pump as well?

I would like the switches to kill everything.

Thanks David. I'll be around tomorrow except for a doctor appt in Tomball at 3:30, then gone for the Chritstmas trek to Irving, Dallas, Sherman (Pottsboro), Bedford, and back to Pottsboro. And that's all in just the first couple of days. Throw in Houston to DFW and back, plus some time in Mansfield. Oh Joy!!!!!

Maybe I'll come see a few of the North Texas racers while I'm there. Why stay in one spot more than 2 hours at a time? :roll:

Sorry. Merry Christmas Everyone!!!!!

mitchntx
12-21-2008, 10:14 PM
But I don't recall seeing this in other cars.


I take that as a compliment as the teal car was loomed like that.

You can see the red wire in this photo ...

http://www.lawmotorsports.net/Pics/94%20Teal%20Formula/web/94TealForm42.JPG

BSharp
12-21-2008, 11:47 PM
Lots of info here. http://www.corner-carvers.com/forums/showthread.php?t=37087&highlight=kill+switch

David Love AI27
12-22-2008, 12:55 AM
Soooo...with the battery in the "rear seat" area and the positive cable from the battery going straight up the main hoop of the roll bar to the first cutoff switch, the alternator output wire needs to be run all the way back to the roll bar hoop? Electrically, this makes sense and is equivalent to the way it was before. But I don't recall seeing this in other cars.

Sorry. Merry Christmas Everyone!!!!!

Either to the pos side of the battery direct or to the bat side of the first cutoff... it works for my car...

AI#97
12-22-2008, 08:53 AM
just wire your alt output wire to the battery side of the cut off switch that is closest (as in electrically and not distance wise) to the battery.

Works like a charm! Just beware that the cable coming from the battery is hot if you start removing things from the switch for service without disconnecting the negative terminal on the battery.

GlennCMC70
12-22-2008, 09:38 AM
just wire your alt output wire to the battery side of the cut off switch that is closest (as in electrically and not distance wise) to the battery.

Works like a charm! Just beware that the cable coming from the battery is hot if you start removing things from the switch for service without disconnecting the negative terminal on the battery.

thus the reason you should remove the POSITIVE from the battery first.

AI#97
12-22-2008, 10:22 AM
just wire your alt output wire to the battery side of the cut off switch that is closest (as in electrically and not distance wise) to the battery.

Works like a charm! Just beware that the cable coming from the battery is hot if you start removing things from the switch for service without disconnecting the negative terminal on the battery.

thus the reason you should remove the POSITIVE from the battery first.

Only been a problem when you have more than one person working on the car that might not expect that....

Rob Liebbe
12-22-2008, 10:30 AM
Thanks for the info guys. I'm going to wire it LAW Motorsports fashion.

mitchntx
12-22-2008, 11:28 AM
Thanks for the info guys. I'm going to wire it LAW Motorsports fashion.

WhadidItellya ... smart!