I always use a Battery Tender for storage. I found my 6V battery to be dead. Had it tested at the parts store and it showed bad. (4 years old) Put in new battery and drove it. I noticed the ammeter was showing 0 charge. I turned on the lights and it went to the usual discharge.Last time I drove it was charging fine(8amps). I disconnected the output wires on the Cut-Out (diode type) to check if it might be closed contacts and that was what drained my old battery. It tested to be open. Now when I try to re-connect the wires to the cut-out I get a huge spark. Is this normal or do I have a problem? I don't remember having this spark before. Oh I've got a generator on my car (6V) Any thoughts would be appreciated. Ron