MaineDoc

I know this has been discussed before many times but I can't find the comments. I always put my green shut off, or my blade shut off on the negative side. My "new" 64 Riviera has it on the positive side. Any thoughts about what is best?

MOXIE62

I've got mine on the positive side only because it is easier to get to. I don't think it makes any difference.

jimh_1962

Negative on mine. Not that easy to get to. I think it does make a difference when it comes to spark and possibly fire. I was always told to disconnect ground.

1snake

cblankin

Negative side

StingU2

Alway the Negative terminal... the reason for this because as soon as you disconnect the negative terminal there is no way you can accidentally short the battery.

If you put the switch on the positive terminal, the battery negative terminal is still connected to the chassis of the car. So if anything conductive comes in contact with the positive terminal it will short the battery.

-Bruce

Frankie the Fink

We have a winner!

https://www.corvetteforum.com/forums...post1590159624

Powershift

Negative side.

The battery posts are different sizes/diameters and most disconnects are made to best fit the negative post (which is thinner/smaller)

But either one will obviously work. Don't overthink it.

Larry

1snake

I respectfully disagree. I've installed at least 20 of the dreaded "green ****" cut-off switches. Just don't buy the ones at swap meets that are 10 for $1. I put them on the easiest terminal to access. Never had a short or a failure of the switch. Probably the worst switch is those ugly "knife" type with all the exposed metal to short out, unlike the the green **** type that you can't short out if you tried because nothing is exposed.

Looking back on my drag racing days, the NHRA requires the cut-off to be on the positive side. I still say it really doesn't matter though.

Frankie the Fink

Sometimes its best to just follow a device's directions....and use a product as the manufacturer intended.

Like those in this 'green ****' installation document...

MaineDoc

You guys have confirmed my thoughts. The Riv will be changed to be just like the 66 and the BelAir-negative side.

StingU2

... I have the green **** disconnect on the negative post on all my cars, I have never trusted the blade type.

-Bruce

ohiovet

Bruce,
I agree and have all my green switches on the negative terminal of the battery.
Ron Francis Wiring recommends installing the battery disconnect on the positive terminal. They state that it is especially important on cars with electronic accessories or fuel injection.
Im not changing mine as they have worked for years with no problems.
Bruce B

StingU2

Bruce... green/negative is the safest way to go!

Stay cool the next 4/5 days!

-Bruce

Frankie the Fink

They sell mostly whiz-bang, powered disconnects (look like old Ford fender mounted starter solenoids) and the old boat style red switch cutoffs so, yes, I guess they do...

phil2302

In broader (not absolute) electrical terms, wires & wire nuts that are green are ground.
I always assumed that was why the green disconnects were.....green.

1snake

For those that are adamant that it has to be on the negative, as I stated above the NHRA rules require it to be on the positive side. Also, the manufacturers of all emergency vehicles (fire engines, ladders, medic units, ambulances, etc.) put the battery disconnect switch on the positive side. Every boat I've ever seen has them there as well.
I still say it really doesn't matter. Put them on which ever terminal has the easiest access.

Roger Walling

I agree that the neg. terminal is best, but on my car I connected the cut off switch to the pos. terminal and mounted it right in the dash where the lighter goes. (who smokes any ways)
I did how ever instal a 16GA. fusible link directly to the batt. to protect the 10 GA. wire.

When I stop the car, I always shut off the switch before I get out. That way everything in the car is powered off except the alt. which I also installed a 16 GA. fuseable link in the circuit .

My shut off has a removable key, further protecting the car from thief..

A-Snake

The NHRA requires the cutoff switch on the positive because it will kill the engine (if still running) in an emergency. Disconnecting the negative terminal will not kill a running engine.

We disconnect the battery for a different reason, so the negative side should be used for the cutoff switch.

65GGvert

That NRHA comment defies electrical physics. They must use some magical wiring system that keeps the battery in the circuit with the negative disconnected. That's assuming that disconnecting the positive in fact kills the engine.