Battery disconnect switch, yes or no?

[stvaughn]

1932 REO, 6 volt battery under the floorboard. Do you recommend a battery disconnect switch and if so, which one? I’d prefer to not have to open the hood every time to turn off the switch. I have used a latching relay on a motorhome towable but I don’t know if they are available in 6 volt. 

Steve

[Marty Roth]

Yes!

All of my collectables have a battery disconnect switch-

both for safety and for security.

 

Minimize the chance of fire,

and slow down a thief-

 

Some are under the locking hood,

others are behind the running board or on the frame where they are not obvious, but readily accessible when you know where to look (or where to reach)

[Curti]

No: I am a tech adviser for the ACD club.  It is surprising how many calls I get because the cars turn over slow due to bad connections at the switch or bad switches.   Put  a diode in the generator cutout to replace the sticking points.

 The wiring harness sold by Rhode Island Wire are fire proof .  There is probably 150 feet of wire in your old car and a mile of it in your modern car.  Why not put a cutout switch in the modern car ?  If the wiring harness in your car are original and frayed, then you might consider a cut out switch.

[Mark Shaw]

I agree with Marty.  A shut off switch also serves to isolate the battery for connection to a battery maintainer during long term storage.

[auburnseeker]

I pull the terminal everytime.  Not a big deal and no switch to fail.  Plus there is no power going anywhere past the post if nothing is connected to it.  Best part is the cost. 

[jrbartlett]

If you do install a battery switch, check the amp ratings and choose one of the higher-amp options. A starter draws a lot of amps. There are a number of different ratings available. And yes, the switches do need to be replaced occasionally, and sometimes the connections cleaned up.  

[46 woodie]

I use a quality switch in my vehicles as many early cars don't have fuses. For example my Model A has none and if there is a short or some other electrical issue by time I get the floor mat up and the battery terminal loose it's too late.

[PFitz]

Yes, to having  one.

Yes, to the heavy duty switches,  with electrician's anti-corrosion paste on the terminals. That not only keeps oil and water out of the connections it works far better at preventing electrical corrosion than the autoparts store goo they sell for battery terminals.

 

NO to putting it through the floor boards.

 

I accidently kicked one off while riding as a front seat passenger and killed the engine at 50 mph. That can risk damaging the generator. Plus, if you have to remove the front floor boards to do any maintenance, such as fill the trans, oil the pedal linkages and throwout bearing, etc., having the switch mounted in the floor board just makes it that much more work.

 

I like to mount them through the floor under the front seat, and near the middle, where it can be easily reached by the driver and also through the passenger door when working in the car. Located there it can't be kicked or stepped on. And to help with hiding them, I make an extension handle for them that looks like a seat adjuster handle.  

 

Paul

Edited October 30, 2018 by PFitz (see edit history)

[TexRiv_63]

Definitely a good idea. On my 34 Packard I installed a heavy duty switch in the drivers seat front base with new 00 gauge cables at the same time I converted to a new Optima battery.

[GARY F]

I have two on each of my 63 Pontiacs. They are under the hood  but I keep the hoods open on everything to keep the mice out. I do clean them once in a while. They are the ones with the green knob.

[1935Packard]

I always have a cut-off.  Saves the battery for long term storage if there's a drain; some anti-theft protection; makes it easy to cut the battery if I'm working on electrical stuff, etc,  I try to have them installed on the floorboard right next to me so i can reach down with my hand from the driver's seat and easily flip the switch without having to get up.  Just do it close to the seat so nothing can get in the way and flip it by accident (which would take a lot of force anyway, but could happen in theory.)  I slip it to off every time I turn off the car after a drive, and flipping it on is part of my starting routine. I like ones like this: https://www.grote.com/family/master-battery-disconnect-switch/

 

Edited October 30, 2018 by 1935Packard (see edit history)

[jp928]

Yes, heavy duty. Lots of amps on 6V systems, so quality is important. I have had an ordinary isolation switch on a high CR V8 for years now, with no issues, and it cranks the same as before the switch.

jp 26 Rover 9

[maok]

I use one of these;

 

My '28 Chrysler battery is under the passenger (RHD) floor board where I can access it via a trap door, quick and easy.

[TexRiv_63]

I have had bad experiences with those green knob things, you need something beefy like this.

[46 woodie]

Tex is correct, I have heard that those green turn style switches will eventually fail. My friend had one and one day he couldn't start his car and it was the green topped switch. Even so, if your battery is under the floor, by time you get to it may be too late. The Cole-Hersee that Tex pictures is a quality switch and won't let you down.

[Spinneyhill]

I don't rely on any technology. The only thing added is a wing nut. The starter lead is held on with a wing nut. Just undo, pull the lead, slip on a length of rubber hose, finished. Can't short, develop bad connection or anything and it is easy to attach a battery charger. Also, the oil dipstick is just along from there so is easy to check when I put it on to go for a run.

[Real Steel]

Yes to having one. 

I've put them on all my vintage cars after an electrical fire in my 1929 Hudson coupe many years ago.

I just mounted another one.  This time, instead of hiding it, I made it a feature! 

The only thing that was modified was the after-market wood floor board. 

The actual switch is attached to an existing hole in the frame cross member.

[Real Steel]

[stvaughn]

7 hours ago, Real Steel said:

Yes to having one. 

I've put them on all my vintage cars after an electrical fire in my 1929 Hudson coupe many years ago.

I just mounted another one.  This time, instead of hiding it, I made it a feature! 

The only thing that was modified was the after-market wood floor board. 

The actual switch is attached to an existing hole in the frame cross member.

Real Steel, where’d you get the recessed plate the switch is mounted in. 

Steve

[Xander Wildeisen]

Does the AACA like the switches, when it comes to judging? 

[Mikefit]

R S that is a professional looking job you did thanks for the pictures.  Mike

[Phillip Cole]

30 minutes ago, Xander Wildeisen said:

Does the AACA like the switches, when it comes to judging? 

Yes, as a safety item, "as long as the installation is done in a workmanlike manner in keeping with the design and era of the vehicle, using authentic wiring, and in good taste."

[Stooge]

I used one in my last project, and intend to use one again in my current Buick project, for as much of a safety/ isolating standpoint as an antitheft device, or atleast an antitheft inconvenience. I had originally tried using a cheaper one and was causing issues before the truck was even on the road, and ended up going with a much more stout and robust Flaming River switch, which also features a removable key that you insert and twist, though I've generally left it in place. "hidden" behind the passenger seat so I can reach over from the driver's seat without it being a hassle.

[padgett]

Cole-Hersee also makes a remotely actuated model for RVs, costs about $100, unit goes next to the battery and just need to add a toggle switch to the interior.

 

Note, NEVER switch the battery out with the engine running. If charging the load has to go somewhere (ELI the ICE man) and I have seen 200+ vdc surges when a charging battery was switched out.

 

ps BTW you can switch out the battery with the engine running and it will keep on going, SCCA requires a kill switch also turn off the alternator/generator.

[60FlatTop]

Grimy, check out either that red car or the green one. The owner told me he wanted the disconnect at arm's length. I learned that you countersink a hole in a wood floorboard with what's called a Forstner bit.

 

I haven't used them myself.

Bernie

[Grimy]

17 minutes ago, 60FlatTop said:

Grimy, check out either that red car or the green one. The owner told me he wanted the disconnect at arm's length. I learned that you countersink a hole in a wood floorboard with what's called a Forstner bit.

I trust you're referring to The Godfather's cars, Bernie.  The green one has gone to greener pastures, but I hope to see the red one at this year's PAS Meet in the NE corner of Indiana and/or the 2020 Meet in Lancaster, PA.  You should come to critique.....

George

[Marty Roth]

On 10/30/2018 at 10:06 AM, auburnseeker said:

I pull the terminal everytime.  Not a big deal and no switch to fail.  Plus there is no power going anywhere past the post if nothing is connected to it.  Best part is the cost. 

 

This is reasonable, but only if the battery is in an accessible location-

In many of our older cars the battery is:

- beneath the front seat

- under a floorboard

- buried deep within the engine compartment

- mounted in an external box, the cover of which is secured by Straight-Tip-headed bolts

 

So in many cases, having an Good Quality external switch, capable of carrying the electrical load required by the starter, makes sense - especially if the battery terminal is relatively inaccessible, as is the case with so many of our older cars-

 

... and as Mark Shaw noted, this way the battery is isolated from the rest of the electrical system so that a battery maintainer can be used effectively for long-term storage.

Fortunately, in this part of the country we rarely have to store our cars since we drive them all year long, but many of you do store your cars for months at a time.

[auburnseeker]

On some cars I can give that they are a viable solution,  just some I think they may create as much of a problem as they solve.   I haven't worried about the battery tender issue.  I wonder if they really make much sense.  I would rather pull the battery and put it in my warm shop if the car isn't being stored in their anyways. If it won't hold a charge for 6 months in a warm shop,  then it needs to be replaced anyways. 

[Real Steel]

5 hours ago, stvaughn said:

Real Steel, where’d you get the recessed plate the switch is mounted in. 

Steve

 

Hi Steve.  I made it from this:

 

[stvaughn]

9 minutes ago, Real Steel said:

 

Hi Steve.  I made it from this:

 

Well I don’t have one of those laying around. Looks like I need to make a few yard sales. ?

[Real Steel]

8 minutes ago, stvaughn said:

Well I don’t have one of those laying around. Looks like I need to make a few yard sales. ?

There are many ash trays on eBay, but few sellers list the sizes.  It took almost an hour of searching to find three good candidates, then I asked them for  the dimensions.  I prefer aluminum, but the one I chose was pewter...it does have a vintage look and its very easy to work with.