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battery cut off switch

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Donny_L

Jedi Trainee
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Is this something I should give thought to installing? I read a post that one of you guys lost his car to a fire due to a short. It scared the bejeepers out of me! How many of you have added this to your car? How hard is it to put one in? About how much should I expect it to cost and what is the best option/style of switch to go with?
 
???? Should be one on your Healey. Which model do you have? Most are in the boot by the battery.
Many fires are caused by gas dripping from the carbs onto the hot exhaust after you shut the engine off. There should be two copper tubes running from the manifold to below the exhaust. There should be rubber tubes from the float chambers to do the same thing.
 
I have a 61 3000 BT7. the tubes frome the floats are there. So are the copper ones from the manifold.,one like new and the other is bent and crimped like it was done intentionally. Do you think I could cut off the crimped end of that one and be okay?As for the battery cutoff, I don't see one. The pos goes strait to ground. Isn't that where it would be. It looks like a new cable, do you think it was replaced and the switch just got left out?
 
My switch went bad so I eliminated it like yours was. I added a fuse box to protect all the circuits which were not fused originally.
IMG_1498-1-1.jpg

Not shown is an online fuse for the red wire feeding the rear lights.
 
Donny_L said:
I have a 61 3000 BT7. the tubes frome the floats are there. So are the copper ones from the manifold.,one like new and the other is bent and crimped like it was done intentionally. Do you think I could cut off the crimped end of that one and be okay?

These copper tubes should be formed into a large lazy "Z" they should not be crimped. This lazy "Z" shape minimises the induction of air into the manifold.


As for the battery cutoff, I don't see one.-----WOT!!!

The pos goes strait to ground. Isn't that where it would be. :yesnod:

Yep that is where they usually place them in series with the ground connection.

It looks like a new cable, do you think it was replaced and the switch just got left out? :yesnod:

Yep, However, the switch is kinda pricy so see if you can find one on E-Bay Cheap!!.
Click to expand...

------------------------------Keoke- :driving:
 
That website that Tim K posted shows one for under ten bucks. That deffinetly fits my budget. Won't that be fine? Is the one your talking about "pricy" because it's the original piece? What's it look like and whats the difference?
 
Donny_L said:
That website that Tim K posted shows one for under ten bucks. That deffinetly fits my budget.- :cooler:

Won't that be fine?
:yesnod: it will serve as an adequate replacement.
Many owners are using them.

Is the one your talking about "pricy" because it's the original piece? :yesnod:--- :yesnod:

What's it look like:

A miniature black plastic door knob-
grin.gif


and whats the difference?

The original:

1] Costs more-$$$$--- Original Lucas Battery Cut Off Switch Austin Healey
Buy It Now $49.99:

2] Has No Red key
3] Will fit original mounting bracket.
4] Different handle and shape
Click to expand...



------------------------Keoke- :driving:
 
I think they can be had for around 50 bucks on E-bay. Don't you have a Moss catalog? The original is re-build-able so it becomes a long term investment. It was meant as a theft deterrent as they are usually in the lockable boot. It cuts the power from the battery to earth (ground) and there is a black and white wire that goes to the coil to ground it as well. This sounds complicated but it is not. I'm, again, not sure how it could cause a fire (if you have a fuse)as any wire will melt before it would cause any damage unless you have fuel available. But others will disagree.
 
:savewave:

A short in the wiring that caused a copper wire to melt would produce a temperature in that wire of 1981 Degrees "F" That temperature is certainly capable of initiating a fire,

Several failed switches I have repaired the conical spring inside has been heated to the point it has lost all its tension.???--Keoke
 
Thanks guys, I think I'll go with the cheap fix for now. Anybody got a pic of how the lazy "Z" looks that Keoke's talking about in that copper line? The one of mine that looks brand new is strait as a pin.
 
Roger's good pictures also shows how not to install a power ground.

As shown the interface between the braided ground cable and the chassis can only occur by traveling through the bolt,

The fasteners in a ground connection are primarily to add fixation and pressure to the interface,
.
If you look along the structure that holds the switch bracket just below that bracket and slightly forward of it you will see the intended chassis connection point for the power ground strap.

It should be free of paint and the bolt fitted with a lock washer.

In the first picture you will see the threaded raised point I am referring too.-Fwiw--Keoke
 
Donny_L said:
Tim K. that looks like a slick set up but it also looks far outside my scope of ability.
Click to expand...
The cutoff switch only provides protection when your car is parked and you have remembered to turn the switch off. There is no protection to the unfused circuits when you are driving or forget to switch it off. My fuse box is a J.C. Whitney special for about $10 and just required some crimps and crimp on connectors. I used one side for the switched circuits and the other for the unswitched circuits. Now if a fuse blows, I can quickly narrow down the circuit involved. I did have a problem with my overdrive solenoid, which was saved because I had added the inline fuse for it (originally unfused).
 
Keoke said:
<span style="font-weight: bold">Roger's good pictures also shows how not to install a power ground.</span>
As shown the interface between the braided ground cable and the chassis can only occur by traveling through the bolt,

The fasteners in a ground connection are to primarily add fixation abd pressure to the interface,
.
If Roger looks along that structure that holds the switch bracket just below that bracket and slightly forward of it he will see the intended connection point for the power ground strap.

It should be free of paint and the bolt fitted with a lock washer.

In the first picture you will see the threaded raised point I am referring too.-Fwiw--Keoke
Click to expand...
LOL!

IMG_3626.sized.jpg


IMG_3627.sized.jpg
 
IN Randys picture somebody forgot to hook up the stop lamp.---Keoke---- :wink:
 
tahoe healey said:
Don't matter much with out a battery.
Click to expand...
:laugh:

I was waiting on the harness, and cleaned up the battery switch (not mounted at all, just dangling on the end of the cables!!).
 
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