Battery cut off switch

Posted by ewrecks On 2018/7/26 17:12:52

Two weeks ago, I parked the Caribbean under the carport and hen I went to start it, it cranked- sort of- but would not start. Since the car is stored most of the time, I installed a shut off switch ( turn knob counterclockwise to disconnect) on the ground cable. Since the cable is the mesh unit, the shut off has a female terminal that attaches to the positive post of the battery and a male end that attaches to the cable terminal.
The unit has been on the car and worked fine.
I assumed the battery was low so I attached it to the charger after disconnecting the cables and allowed a slow charge overnight.
Next morning same problem so I cleaned all terminals and tried again....nothing. I pulled the battery and took it to NAPA to have it checked......tested fine.
I returned the battery to the car and still no luck. NAPA closed at noon so I took the battery to AutoZone where they said battery was fine...just needed charged. They charged the battery...no charge LOL....and I reinstalled it with the same result....no lights...no turning of the engine.
I retrieved a floor jack and jack stand and got under the car to check connections to the starter.....all were fine.
I was ready to have the car towed to a repair shop when I decided to pull the shut off switch. Attached the ground cable directly to the battery and it fired right up.
I never have had problem with the shut off switch on any vehicle and am curious as to whether attaching to the positive pole could be the reason. Secondly,,since I like to cut power when the car is stored, is there any reason that the same kind of unit cannot be attached to the negative post....even though that cable goes to the starter on the 55 Paxkard.
The units are designed to fit on the smaller diameter negative post.
Dumb questions but ...
Thanks
RJR