Trying to put a disconnect on to keep battery charged up while my truck sits. Can I do this through the negative side so I dont have to run every accessory through the switch? I am doing this to prevent drain not to kill the truck.

1/26/2009 11:27:16 AM

yep

1/26/2009 11:49:30 AM

http://www.batterytender.com/

my dad had one for his motorcycle and loved it

1/26/2009 11:49:41 AM

Thats not an option as it will be parked outside at my apartment. If that were the case I would just open the hood and pop the negative off but I am going to run it to the bumper so I dont have to do anything but flip the switch.

1/26/2009 12:07:34 PM

[Edited on January 26, 2009 at 12:19 PM. Reason : a post so nice, i made it twice]

1/26/2009 12:17:44 PM

You are supposed to do it through the neg. side anyhow.

First (or maybe second) thing I was taught about working on cars. When disconnecting the battery, negative first. Why? The pos. has a tendency to spark and arc and batteries can and will explode violently given the chance. Wether or not it has been especially relevant in my career is debatable, but I haven't had any unfortunate incidents as of yet. This brings to mind some fun memories- first, seeing the caps off a battery that detonated literally stuck in the ceiling of the first shop I worked in, after they were thrown 25 feet straight upwards. Second, a fellow mechanic laying his air ratchet across a battery, when I warned him against it he said "But its aluminum, its not metal!". Third, and it seems like this has happened a million times, a fellow tech standing over a battery, cigeratte hanging out of his mouth, telling me how the most dangerous thing about a car battery is electrocution.

"But its six hundred amps, man! Thats enough to power sixty one-hundred watt light bulbs!

1/26/2009 12:19:34 PM

My dad saw a guy get some pretty nasty acid burns from an exploding battery. Battery sparked when he was hooking it up and blew up in his face. The guy washed it off pretty quickly, but it still burned him. Melted the paint off the fenders of the car in the meantime.

1/26/2009 12:25:37 PM

:facepalm at car mechanics:

1/26/2009 12:28:07 PM

HCL+Zinc-->Hydrogen Gas + ZCL

hydrogen gas go boom

1/26/2009 2:41:58 PM

^^^^same here, disconnecting the negative and then covering the terminals with a rag before working on anything underhood was one of the first things my dad engrained into me.

the old school maintenance style batteries that used antimony instead of calcium could be especially dangerous. most new batteries are pretty safe even if you do something stupid, but special care should still be taken with any lead-acid battery that's just taken a good charge. like being hooked to a charger, just finished a drive, etc. reason being is the levels of hydrogen gas are always higher after a battery has been taking some amps.

as for the original topic, you'll be fine just using one of the cheap/basic switches on the negative side for what you're trying to do. the really nice ones for race cars, etc. include extra terminals to isolate other components in the system like the alternator, coil, etc. but you don't need anything like that. check out summit racing, they sell their own brand of decent remote mount rotary ones for like $20 i think. or, you could just get a nice quick disconnect terminal for about $10 probably. check out local marine suppy places for the terminals. walmart might even have them in their little boating section.

1/26/2009 3:55:38 PM

i, too, have been fussed at for laying a 18" extension on top of the battery

1/26/2009 5:54:01 PM

pussies, Jeepman can vouch for the fact that i use a large screwdriver to see if a battery has a good charge or not

1/26/2009 6:20:57 PM

I ended up running just the accessories through it, I wanted it in the wheel well so I wouldnt have to raise the hood every time.

1/26/2009 8:39:14 PM

just put a main power switch on the dash like they do on racecars.

1/27/2009 11:59:44 AM

I have a chunk missing from one of my wrenches from where I dropped in on a battey and it tried to fuse itself on. Good stuff.

1/27/2009 12:18:32 PM