Battery Cutoff Switch

Trying to eliminate anything not necessary to simplify my new jeep project. I put the battery cable directly on the post and I got nothing when i tried to start it. So i Put the cutoff switch back on and it fires right up. What gives? I shouldn't need the extra thingy there.

 

You actually have 2 cutoffs there. The knife switch is one and if you remove the bolt in the middle of that other part it will cut power too.

 

Thanks!

 

I use the blade style master switch on all my jeeps

 

You are correct that it does not compute and everything looks clean. Your main failure point would be the knife switch which works when connected.

Your statement "simplify my new jeep project". Get rid of the side-post adapter and get a cable with the proper top-post connector. Use a good heavy
cable and never look back. Do not use the temporary, strip the wire and bolt together style for anything more than trail repair or testing.

Mine are custom made. A little overkill...I have repaired plenty of wiring.

 

Some caution is warranted using that style cutoff with a winch. That copper blade can get REALLY warm, most especially if the contacts are not clean. I'm another that overkills wire gauge. All my heavy draws in my 3B are individual 00 leads, winch, starter and welder (which is also the alternator). The current (excuse the pun) setup with 600 amp main fuse:

 

You are correct and I forgot to mention getting rid of the switch. The heat transfers through the switch and wire to any components connected to it.
I have heard conduit rattle and jump on inrush starting amps for a/c units. In the effort to save money, electricians would run the minimum size wiring
called out by the manufacturers data tag. The wire would heat, transfer to the windings of the compressor motors and would burn the insulation off.
Nasty burn outs in the refrigerant system and difficult to clean out. Often times the fuse would blow do to the the heat generated. Wire temps and high
ambient temps do not play well together. One building was an electrical supply house.

Edit to say: Do not use the side post of a dual post battery for a winch. The conductor in the battery is small and will perform as a fuse or fire. Picture meltdown. Also, I have taken apart
many inline switches that have failed. When you see how they are constructed you will wonder how they could possible to carry the current required.

 

I just put a Battery Tinder on my Jeep when it is stored, no problems, no extra stuff.

 

Per your original issue the only thing I can think of is a dirty contact somewhere.
That being said I have that style disconnect on mine. I think it's a good safety measure and I keep the switch open whenever I'm not using the vehicles. I do not have any big electrical accessories on mine so I don't have the overheating issue.

 

I've used the blade type, and they are okay, but a nuisance to open the hood.

I recently mounted one of these in my YJ. Inside the cab, on the transmission tunnel, connected with heavy welding cable and soldered lugs. I love it.

https://www.ebay.com/itm/115163770750?hash=item1ad04baf7e:g:x7UAAOSwXjlhzfEM&amdata=enc:AQAHAAAAwI+SS0zse0Q83g/PJL/HeFk9HQtQYHhuHVojKu5UsXBea2lnSCgmlPntAG6/TvIcVIAi49VOeXG2Wpa1sHfGAfr8cRjoWHDmPIJflWqJKsyZH5kr2UOAO3IBarXqsHOvrK3lG6vTiYyFJYhLrIZRY83cZeG8ysTdeVvUkm4m1TITFve89z3MccqsnMEtspWVSDMniC3CYleENHbnsZkuW1UBBOfEelatKSVAnVibWUsxAQplRdlo9IMX8Jvuc3yL2g==|tkp:BlBMUKigw8-vYQ

 

I do see the advantage of a cutoff inside the cab. The downside though is longer battery cable runs and more opportunities for an accidental short.

The upside of having to open the hood is that it's a great reminder to check your engine oil.

 

Been thinking of using one of these cut off switches on the M38A1 since it doesn't require a key. The USMC version has a metal loop on the gear stick to pad lock it to the dash so it can only be driven in reverse. A little extra insurance wouldn't hurt.
Used to have those on the CAT equipment I worked on years ago.


Dave

 

Every fire engine in our department has one, used every time.

 

I'm picturing a very interesting police chase...

 

With an overdrive. Back when people knew what standard transmissions were, you could always count on some strange looks when you shifted gears in reverse.

 

The idea of a switch is good. The prices look to be a little on the cheap side... you get what you pay for! Look for a US made brand and have a backup plan.
A short pigtail with eyelets would work. I went through two batteries on my M/C before diagnosing the kill switch on the handle bar. Cleaned the switch and now
have a spare battery. Intermittent problem and the battery showed fully charged.

 

A couple days ago I was starting my diesel tractor. It had been a couple months since I ran it so I put the key in start to crank it a second and make sure the battery was good. The starter solenoid stuck in the start position and it wouldn't stop cranking. I had to grab a wrench and disconnect the wire from the starter. Would have been nice to have a battery shutoff switch. The battery on this one is hard to access; I'll have to get a remote switch.

 

I run a big manual cutoff switch on the dash of my 2A, on my CJ5 I'm running a disconnect solenoid with a small toggle switch on the dash to completely cut off power to everything else. The starter solenoid and everything runs through that disconnect solenoid. Either way works fine, the disconnect solenoid means you don't need to run heavy battery cables into the dash, but it does add some clutter under the hood with the solenoid.

 

Ouch! Stuff happens, believe me! Bolt cutter disconnect?

 

Is the relay rated for continuous use?