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Battery Cutoff Switch

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Hi Dave, I have been thinking that an economical solution that will also look stock is to use the metal battery cut off switch that looks like an old Model "A" ignition sw and modify the shaft to accept the Healey Knob. They sell for less than $25.00 at most of the usual suspects stores and are of good quality.I will have a look at my friends Rover and see if he has one of those installed in his car.--Regards---Keoke
 
On some of these cut off switches there are only two terminals. I've got a third with a maybe 14 gauge wire on mine. I've not paid attention to where it goes. What does one do with it if there is no place to put it?
 
TH that little Black and white wire can leave you stranded many miles from home ifin you do not know that it grounds the secondary of the ignition coil when the switch is in the off position.Some times it does that thing all by itself in the on position and that can be most frustrating. so just tape the end up and tuck it out of sight---Keoke /ubbthreads/images/graemlins/laugh.gif
 
Keoke,
Very good advice.

TH,
The original switch has the smaller wire which gets grounded when the battery switch is off. The other end of this wire goes to the points side of the ignition coil. Supposedly if you push started the car it would start & run on the generator with the battery switched off. It is very easy to hot wire (bypass the ignition switch) a Healey by jumpering the top & bottom fuses on the fuse block. This extra wire keeps the ignition disabled as long as the battery switch is off.

The problem is, as Keoke says, that this ignition terminal sometimes gets grounded by the battery switch when it is in the on position also. No end of intermittent ignition problems.

There are good aftermarket switches that DO have a third terminal for a similar purpose. If a race car gets in trouble, the alternator will continue to power the ignition even with the battery disconnected. These switches must be installed where they can easily be reached by the driver or rescue workers. So, whether for theft prevention or car crash safety the third terminal "may" be useful.
D
 
Yes TH, I am saying it is not necessary and it eliminates a potential baffeling failure mode in the cars when terminated in the original battery cut off switch.---Keoke
 
Keoke, Hurry! I'm running out of breath, feeling faint, hurry, hurry...

If my old one gives me any more aggravation, I'm just going to bypass it. My next two major investments are a new (and this time correct, unlike the PO) muffler and then a new paint job. The old battery shut off looks fine, and I can live without it actually working. Not that it wouldn't be nice to have everything working properly.
 
Shg , your just tooo slow. You know if the false security that that switch provides does not have you mesmerised,all you need to do is to connect both ground cables to a common terminal on the switch-instant bypass and the aggrivation generator is still there. be sure and hide the little black and white wire, /ubbthreads/images/graemlins/laugh.gif---Regards Keoke
 
Funny you should say that. It's what I did last summer, but when I put her to sleep for the winter, I decided to try to actually hook it up right again. Big mistake. I keep hoping some little elf is going sneak into my garage in the middle of the night and fix the switch. I'm still waiting.
 
If I follow the discussion, the battery switch passes through the ground from battery to chassis when it is in the "on" position and when in the "off" position, it grounds the coil so the engine won't start. Is my understanding correct?

Is the ground to the chassis interrupted when the switch is in the "off" position as well? Once I get it apart and back together (hopefully) I would like to be sure that I have it assembled correctly. I figure I can check it with a voltmeter.
 
Yes - You are correct. There are several posibilities of assembling it but only one of them is correct. Also the two large terminals must not be connected backward in the car. Check that the switch does not over rotate or ground the small terminal when in the on position.
D
 
I found a new reproduction switch on Ebay. It is exactly the same except the knob. I romoved the circle clip and exchanged the knob for the original. An exact fit! $35.00!
I'm happy.
 
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