Electrical question

[SK Super90]

The moment I get both battery cables connected to my battery (12-volt), the battery begins to make a sizzling noise.
Is this an indication I've got a short, that something is drawing power, or simply that my battery is shot?
This is not a maintenance-free battery - I have the ability to add demineralized water to the cells, and have done so in the past.
Despite the sizzle, the battery has enough juice to turn over and start my tractor - a 1963 MF Super 90 WR with the Perkins diesel - something I don't think a weak battery would be able to do.
Any thoughts or observations would be greatly appreciated!
Cheers,
Paul

 

[Jerry/MT]

You haven"t provided much useful info. I"m not quite sure what you mean by a "sizzling noise". Are you sure the noise is coming from the battery? Battery"s don"t generally make noise! I doubt that this indicates a bad battery. A bad battery would fail to charge or once charged would discharge quickly.

Does your ammeter show a discharge with the key switch off? Does the battery consistently need charging before use? Or is that why you disconnect the cables? Does the battery discharge if you keep them connected? If it does than you must have a short somewhere that"s draining your battery. Check any wires and/or cables that have a direct connection to the battery. Look for broken insulation that could allow grounding the wires , terminals grounded against the frame, etc