• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

TR2/3/3A Bad Day in the Garage

Share this page

jfarris said:
...I have a battery cutoff switch to add to my TR3 which is still positive ground...
Click to expand...

Okay, I just did mine and I should note - the usual green & gold cut-off switch sold by most places is designed for the (smaller) negative post. Nevertheless, I used it on the positive post by expanding the opening, redrilling the holes to align and grinding the spot where the bolt & nut seat to again present a perpendicular surface.
 
And as I also just tried to install mine, I found out that the body of this mechanism is out of pot metal and will not stand being pried open very far to fit on the positive post. At least they are inexpensive. In my next installation attempt, I will enlarge the hole, don't think I have a drill bit that large, but I have a Dremel.
 
Someone, I forget who offhand, offers a positive post version.

But personally, I don't see that it makes a lot of difference. The reason for normally putting it on the ground side is that it will still break the circuit if you drop a wrench between the body and the battery post. Not all that likely, IMO. Either way, it will still interrupt the circuit if the solenoid contacts weld or whatever.

Another option would be one of the racer-style remote cutoffs. You could mount to be accessible from outside (thereby removing the time to open the hood) or build a bracket to keep it under the hood.

Here's one from Walmart that claims to fit either post.
https://tinyurl.com/lpdmtm6
 
Bummer. That's one of those things that I think about, and how to avoid, and it seems to be much like stage-freight. The more you worry about it, the more likely it will happen. I don't have a cut-off switch, but I never tighten the negative battery terminal. I like to push it on with a 1/4 turn twist. The 1/4 turn probably does nothing but make me feel good, but it is snug and has never been a problem.

A few months back, I was working on my car, and needed to do something with the key in the 'on' position. So, I pulled the white wire off the distributor (to not power up the electronic ignition) and switched the key to on. The ammeter pegged, and I switched it off. Scratched my head, and turned it on again and watched the ammeter peg. I shut it off almost instantly, but could already smell insulation burning. The wire I pulled happened to fall on one of the metal latches that holds the dizzy cap in place. That wire is not fused, and melted all the way to the control box. The wiring harness only had a few thousand miles on it... Oh well, I ran a new wire outside the cloth wrapped harness, and tried to hide it as well as possible. -The bottom line, it only takes a second. I was lucky and did not burn my hand, but there is no way I could have switched a cut off that fast. I'm not sure how to prepare for a 'catastrophic event', but glad my (or Geos) car didn't burn up.

My days in the garage seem so far away...
 
Back
Top