battery cutoff switch

[71tr]

So I'm looking for a battery isolator switch to install in my restoration. This is the switch with the removable key typically installed in the firewall which allows you to deenergize your electrical system quickly and easily. Looking to the usual sources I was shocked that Moss wanted $82 while Vic-Brit was asking only $17. Choice settled, right! Well, today shopping at my local AdvanceAuto I found the same switch for $7 and some change.

 

[sammyb]

I purchased a bunch of those ones that connect in between the cable and the battery and unscrew (the green knobs) for $5. They work great, but you have to pop the bonnet to use them (although in my '69 Corvette, the battery is behind the driver, so it's easy.)

 

[71tr]

Yes, I am familiar with the green thumb screw switch. I have one of those as well but was looking for something I could mount in the cockpit, this fit the bill.

 

[drooartz]

I'm a little unclear (it's early still here) on how this would be mounted. Would it mount so the terminals were exposed on the engine side of the firewall and the key on the passenger side of the firewall? On the ground or hot lead?

Thanks,
-Drew

 

[71tr]

I understand the time difference Drew, used to live in Cali while working for an east coast firm. Those early morning meetings drove me nuts. The preferred mounting would be as you say; firewall with terminals in engine bay and switch in cockpit. It can be wired either to negative or positive side of battery. Just need to figure out best location.

 

[Alan_Myers]

Hi,

I'm fairly certain what you are looking at is a Hella battery disconnect switch/with alternator disconnect. It has a large red plastic key that's removeable.

These are used on race cars as an external means for safety crews to shut off a car's engine in the event of an accident. They are typically mounted in a highly visible and accessible place and marked with a decal, required in many classes of racing. The Hella is not legal in some classes of racing, due to its removeable key.

There are a variety of types. The least expensive just disconnect the battery and don't have a removeable key. More expensive disconnect both the battery & alternator. There are also remote-type disconnects, either with a mechanical pull lever or, more recently available, a Painless Wiring solenoid-type that allows the big red button to be mounted nearly anywhere. There are also disconnects which are more anti-theft oriented, with a small toggle switch, a key operated switch or something like that.

Of course, hidden under the dash many of these switches can make a good anti-theft device, but you probably won't want to carry the Hella key around in your pocket! I'm pretty sure you will need a disconnect that accommodates an alternator, so check out www.racerpartswholesale.com They have the Hella for about $40. www.summitracing.com has the Hella without the alternator circuit disconnect for under $20. It looks like www.jegs.com offers a variety, as well. At each website you'll find alternative brands and types if you search for "battery disconnect".

Besides Painless and Hella, you'll also find disconnects made by Flaming River, Moroso and others.