can someone tell me the place to connect a battery cut off switch on 41 60 special positive ground. positive or negative ? thanks john
Typically it is the ground that is switched but I am curious as to the opinions of others. I don't think it really matters as opening either cable will isolate the battery from the circuit.
For me it would depend on the type of switch. If its one with exposed metal I would put it on the grounded side. That way if something was to fall between the body or engine and the exposed contact worst case it just connects the battery back up. If it was the not grounded terminal and that happened you got a big bang. If its fully enclosed and does expose the ungrounded terminal any more than it would normally be I don't think it would matter, I would put it on which ever one gave it the cleanest look and easiest fit.
I have had enough things fall on battery terminals now that I buy insulators for them now especially top post stuff where its easy to have something land on em. My local parts store has some nice ones on their marine display rack that are about $8 per pair. The intended install method is to slide em on before you install the cable to starter (or whatever). You can always slit the part that goes over the cable and then zip tie it to hold it on if you want to make the install easy or easy removal for something like a show.
This has been discussed on this forum at length before. My view is the best place is somewhere inside the car where you can get at it. There have been cases of cars going up in flames because the hood couldn't be lifted to get at switches either on the battery or somewhere else inside the engine compartment right where the fire is. :-[
I believe the typical dealer-installed switch fit on the firewall as per the picture below (not my car, but something I saved from the web). There is a factory knockout in the firewall at this position. The switch can be reasonably accessed under the dash when in this spot.
Switching the battery primary to the starter (negative on a 1941) is the way I would hook it up. Make sure you get a switch that can handle the full cranking current of your starter.
Paul
Quote from: Paul Phillips on August 03, 2014, 03:52:37 PM
I believe the typical dealer-installed switch fit on the firewall as per the picture below (not my car, but something I saved from the web). There is a factory knockout in the firewall at this position.
Paul
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Its a great position Paul but are you suggesting that Cadillac would fit one of these switches as an extra in 41?? and leave a knock out for it?? I find that hard to believe unless I can see it in a Cadillac accessory book.
I was not even aware of such switches until 30+ years ago.
There's a spot engineered in for a switch?!?!
Negative side, for the reason that if something does touch the switch it will not matter. Plus if you read the shop manual, when working on electrical items it always instructs to disconnect negative battery terminal. Not sure if I agree that you should install it inside the passenger compartment. If the car is in a state where it may catch fire and turning the switch off will be a positive benefit to extinguishing the fire, the switch should only be on when it is time to drive the car, and repairs should be made.
I know of a 1939 Cadillac convertible coupe 75 series here in England that went up in flames because of a small (at the time) fire from the carburetor. The owner was unable to get to the cut-off switch inside the hood because of the flames. The fire got to the wiring loom which melted and fused the wires through and under the dash and started a fire there which gutted the cabin of the car and all the central area of the car. This $100,000 car was wiped out.
It always gets put where the driver can get at it on my cars.
It all depends on which wires you are trying to protect. Having the switch in the passenger side is fine but don't forget then that you will have 8-10 feet of unprotected cable (by the time you snake it around,etc) inside the engine compartment. Also, that is a long run of cable. If you have a marginal electrical system/weak ground/starter,etc then the length of the cable may exaggerate the problem.
Jeff
Quote from: Jeff Rose on August 04, 2014, 09:20:15 PM
It all depends on which wires you are trying to protect. Having the switch in the passenger side is fine but don't forget then that you will have 8-10 feet of unprotected cable (by the time you snake it around,etc) inside the engine compartment. Also, that is a long run of cable. If you have a marginal electrical system/weak ground/starter,etc then the length of the cable may exaggerate the problem.
Jeff
If you look at that picture Jeff you will see that the switch is no more than 20" from the battery position on the 41 and only about 14" from the starter. Remember, on earlier cars the battery was under the seat and these cables were regularly 5 to 6 feet in length and still did the job.
Oh, ok, Gotcha.
Jeff
I'm still wondering about the knockout on the firewall for a cut off switch. I have doubts. I can't imagine that the engineers would expect the owners to need to do this.
Quote from: Joe Ceretti on August 05, 2014, 10:34:19 PM
I'm still wondering about the knockout on the firewall for a cut off switch. I have doubts. I can't imagine that the engineers would expect the owners to need to do this.
Nah, me neither Joe.