Battery disconnect switch

[Gary/IA]

The vendors suggest the disconnect switch should be between the battery and the starter, I think I remember a post that made an argument for putting the switch on the ground side of the battery. Which position would you recommend and why.

[Bruce Adams]

I am very pleased with the brass $25 switch on my firewall above the starter button so I kick it off and on with my foot. Its easy and does the job as desired.

The switch with the green wheel can be made of pot metal and fail easily.

[Pete]

I put it in the ground lead just before the frame connection.
I use a switch rated at 200 amps because it has to carry full load
starter current.

[Mike V. Florida]

It would just depend on where you are mounting the switch.

[Jack '29 Sport Coupe]

I put mine on the firewall just above the clutch and can operate it with my toe.

Jack

[1931 flamingo]

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Tudor sedan, mine is mounted UNDER front seat, good location. Easiest to turn on before getting into car and easy to turn off before getting out. Works for me
Paul in CT

[Art Bjornestad]

I installed mine on the front seat riser directly above the tranny and ran an insulated ground lead to the switch.

[dan]

Would someone with a floor-mounted switch (that you're switching with your foot) post a picture? I'm interested in seeing what this looks like.

[Jack '29 Sport Coupe]

Hope this helps.

[dan]

Thanks, Jack.

[Patrick]

I mounted mine on the side of the seat riser on the ground side of the battery This works great for me.
When I leave the car everything is turned off. No one can blow the horn or turn on the lights.
My car is now 12 volt neg ground.............

[Mountain Dew]

I'm a firm believer in not drilling holes in my Model A. I mounted a battery switch in a pre-existing hole in the front crossmember on the drivers side. It is easy to get to and has came in handy when the starter switch stuck and I had to switch off the battery.

[Afordman31]

Mine is in the crossmember right between my legs, easy to reach and pretty much out of sight. Almost tight to the seat riser. 31 Pickup

[Barry in St.Paul]

Mountain Dew, I'm missing something; if it is 'easy to get to', sounds like it is located inside the passenger compartment, but if in a 'crossmember' of the frame, you had to drill a hole in something....??? Did you put a hole in your floorboard and floor mat then? I have my disconnect switch mounted in the rear-engine mount, right next to the starter. Kept my cables short instead of running a long cable back to the seat area from the starter.... but does require me to open the hood every time I am going to drive, which can be a pain... I agree with you, though, I hated to drill a hole in the seat riser of my coupe AND then have the switch and bare cable ends in my "tool box' area under the seat. Ditto for firewall mount, cutting holes like that bothers me. :-)

[HoarseWhisperer]

I don't like drilling holes, either, so I opted for the mount that utilzes the existing lower bolt of the starter. I have to open the hood, but it gives me the opportunity to inspect the engine compartment frequently (fan blade cracks, leaks, if the engine is still there , etc.)

[Dave in MN]

Originally Posted by Gary/IA

The vendors suggest the disconnect switch should be between the battery and the starter, I think I remember a post that made an argument for putting the switch on the ground side of the battery. Which position would you recommend and why.

Gary/IA: I think I understand your question and it is a good one. I did not see the previous post regarding placing the switch on the ground side. Without serious thought, I can not come up with any good reasons to have it on the ground side of the system. When installing mine, I did not even consider the alternate side of the battery as I took the easy path and connected the battery cable that normally runs to the starter to the new switch and then added a short second cable from the cutoff switch to the starter. I mounted the cutoff under the hood using a modified available bracket for the switch. I placed the switch on the steering column with a "U" clamp for easy reach when the hood is raised a few inches. I may relocate it to mount through the floor boards when I have time as it is a bit of a pain to switch it on and off. Having two vehicles, one with a shutoff and one without, I often climb into the car with the shutoff and step on the starter to find I have no power...duh!
A couple "after the task" reasons to mount on the starter side of the battery: First: Placing a battery charger lead on the lug of the disconnect switch leading to the battery keeps the electrical system off to the vehicle yet allows for charging from under the hood rather than lifting the floor mat and battery inspection cover. Second: I try to think of ways to do any modifications from stock in a manner that are reversible if the next owner wants to restore it for originality judging. Mounting as I have with a clamp is easily reversed. Third: I guess if you wanted power available to a circuit on your car all the time yet you wanted to be able to shut down the rest of the system, the starter side disconnect would conveniently and safely allow for this by pulling power from the negative battery terminal or the hot side of the disconnect switch for this "always on" circuit... Hmmm...Can you imagine what would happen if you switched the ground side cable and ran a jumper off the ground side of the battery to complete a small circuit as discussed above and then stepped on the starter with the disconnect off. I think the result could be a melt down of the small circuit wiring. Hey...if this auxilary circuit wire was run under the seat, you may have developed a simple, one time use, seat warmer! Good Day! Dave in MN

[Gary/IA]

Thanks to all for the different suggestions. I guess after reading them, I have elected to mount my switch in the existing square hole in the cross member of the frame. This will place the switch handle on the floor between the front seats (29 tudor). I guess I will have to make an extension for the switch handle shaft as I would prefer the switch handle to be just above the floor mat. I will then have the switch in the ground circuit due to location of switch.

I can see the under the hood location would be the simplest, but with my memory I would have to get in the car twice for each trip.

[zzlegend]

Originally Posted by HoarseWhisperer

I don't like drilling holes, either, so I opted for the mount that utilzes the existing lower bolt of the starter. I have to open the hood, but it gives me the opportunity to inspect the engine compartment frequently (fan blade cracks, leaks, if the engine is still there , etc.)

Ditto for me. Mounted just like HoarseWhisperer. The only difference is i dont have a hood to open on my beater pickup.

[MikeK]

Here's my no-holes in any metal solution.


With the rug dropped back in place it is invisible inside and, of course, under the hood. I can reach it while seated, under my left leg or easily while standing at the open driver's door by simply lifting the corner of the rug which I no longer snap down in that corner. The extra cable going under the seat is a feed for my GPS, Cell, Tire pump, etc.



It's hard to see, but there is a 3"x4" x 1/4 clear lexan plate as a washer between the inside of the crossmember and switch. You can't see the three dimples drilled in the plastic to match the switch top and prevent rotation. Topside, a really big, thick fender washer and a piece of inner tube under the jamb nut on the switch shaft, visible in the first picture.

[Kevin - Illinois]

Looks good Mike! I think I'm going to do that also.