If you're worried about overcharging, there's no need to take it to a professional to find out. Just put a voltmeter on, rev the engine just a bit, and if it stays at 14.5 volts or below it is fine. Even better, install a permanent voltmeter inside the car.

Get the alternator checked out properley. There is a bit more to an alternator then fust brushes & bearings. There is things like diodes & rectifiers that fail. So take it to an auto elec cos if its over charging you will only cook another batterie.

OK thanks for the advice, ideas, stories, and experiences.
I had the alternator serviced, rebushed a few years ago so that is fine, I guess I was just slack and did not check the water level, I thought something may have been short circuiting but that would blow a fuse instead of boil the battery..... so I'm off to buy a new battery - small price to pay to sell the little beastie.
by the way someone asked if I have any spares, I have some extractors and the orginal carby that are not fitted but the new buyer may want them also, depending on what they want to offer...
thanks again!

This happened to me last year -- and it was not overcharging. My mustang was in the garage for six months without driving, then in the spring the battery wouldn't charge up and then I discovered it was out of water. I forgot that checking water level was part of regular maintainence. I had to buy a new battery. The plates were sulfurous-looking and after I added water, it still wouldn't take a charge.

Lesson learned: check the battery levels every few months and top up as needed with distilled water ... or risk a battery going bad before its time.

yep it sounds like an overcharging alternator!! That happened to me one time traveling 70 miles away battery blew the caps off the top , battery acid all over the plug wires . looked like christmas lights under the hood ,lol

Sounds like you have a crook regulator, letting the alternator overcharge. Make sure that the charging voltage doesn't go over 14.5 volts

has anyone ever had their battery boil dry - I though I had a bad batch of fuel but I checked the battery the otehr day and was baren after 2 45min drives - I dont drive it much so thought the ute just needed a good drive to charge the battery. So I've topped up the cells with distilled water but the inside looks cooked so thinking a new battery is the go - damn thing decides to do this when she heard I was selling her!
The radio started cutting out too so I will experiment by removing the radio fuse and see if it happens again. if it fixes it I guess the new owner will need to get a new radio fitted........
thoughts? experiences??