Battery wrench- save your face

The OP appears to be concerned about touching the negative terminal, that has been disconnected from ground, with the wrench when using the wrench on the positive terminal.

intheburbs wrote:

j-d wrote:
The mechanic used a box wrench on the positive before disconnecting the negative.

Therein lies the problem. Disconnect the ground first, and move it away from the battery and you'll have no worries.

Respect a battery just like you would a firearm. It has the potential to seriously injure or even kill you.

Nobody caught my pun. I thought it was a good one. You all make me sad. :(

Correct, Kit! My wife and daughters know about Negative Off First/Positive On First.
I, STUPIDLY, blew up a battery testing a starter. Got in a hurry, got dumb.

Horizon170 wrote:


Hee hee, except on those OLD Fords with Positive Ground.:)
I think that went away around 1950 or so.
BTW, I always hold my big paw on the other end of the wrench but still remove the ground cable first.

My 1956 TR-3 Roadsters had a positive ground. One Break light, and of course no safety-belts.

Where was Ralph Nader?

intheburbs wrote:

j-d wrote:
The mechanic used a box wrench on the positive before disconnecting the negative.

Therein lies the problem. Disconnect the ground first, and move it away from the battery and you'll have no worries.

Respect a battery just like you would a firearm. It has the potential to seriously injure or even kill you.

intheburbs, you are correct!! I taught my two sons the negative is first off and last on. Now I am teaching the same to one of my grandsons.

I guess I'm the wimpy type as I wore GOGGLES and use "special" tools. We had "special" aprons and FULL face shields when washing and filling batteries. Funny that all of our battery fill devices were made out of plastic, I mean what would it matter, the cables were just laying there and not connected to anything, couldn't be any potential if even one cable was removed. Humm very strange. Especially after seeing the top of a battery gone and plastic shrapnel flying all over.
As long as there is energy in the battery there is danger between the terminals. The most danger is when the battery is gassing from charging or discharging as hydrogen is produced. An acetylene torch can be used to melt the connector links off of industrial type cells BUT that is after the battery has stabilized and not gassing. All the caps are removed and its allowed to settle to room temp.
Oh well, carry on as you want and hopefully none of our newer members are injured as they learn.

JamesBr wrote:
Disconnect the ground first and you wont have any need for special tools.

So when the negative cable has been removed there is now no energy potential between the positive and the negative terminal? So it must be ok to touch the wrench against the negative when you are disconnecting the positive? OK, I got it now. Thanks.

Disconnect the ground first and you wont have any need for special tools.

Removing the ground first is beginner stuff and I'm sure a lot of people that are new to RV's dont know that but that's not the only problem. Most standard combination wrenches that people would have are just a little too long for safe battery service. My Protos are short as far as standard size goes and they will still touch.

Side access compartments probably just make dropping a wrench easier.





Four good old Sams Club group 27 going on the 7 th year of service in my 48 volt pontoon boat.

"Hee hee, except on those OLD Fords with Positive Ground.
I think that went away around 1950 or so."

The wonderful new 1956 Ford switched from positive to negative ground and added three cells to the battery. Ford bragged "We have seven more cubic inches in our engine than Chevrolet!"

We had an iron-clad rule

Safety Goggles not safety glasses. Goggles. The ones with side protection and an elastic strap. A popping battery can blow regular glasses off your ears and nose so fast it'd make you dizzy. Anyone caught in the battery area without goggles on was fined ten dollars which went into the coffee and danish fund. Back then this was enough money to matter. We had half a dozen or so caught (including me - my pleas that I only ran out there to tell someone they had a phone call fell on deaf ears)