Let me guess! The one in the boat wsas put away after use without recharging? In which ase it will undoubtedly have sulphated and be beyond useful salvage. The other one may have been syored pre-charged which will have helped preseve it. However, just cos it apperas to be charged doesn't mean it'll have full capacity under load. I reckon you need to put a load on it and see how it behaves then.
Guy, I have no idea what condition it was stored in, I just can't remember day-to-day events in 94-95-ish. It's a big 6v 10ah battery and I'd used it about 20 mins on a lake (it as 4 x 385 type motors)
PMK: I'll try to find sunnybob frank and PM him, thanks mate.
But I once got my hifi LP record player deck down from the loft, found it worked (spun) but needed a new stylus so I bought one, which was quite dear, IIRC. On trying the record deck with nice new needle that didn't ruin my LPs, I found the motor were giving a good impression of being tired and didn't spin the platter at the right speed, then it just gave out.
The lesson I learnt was test the blxxdy thing before you part with any more hard-earned on old or iffy items. I don't mind buying a new battery for it but not if I'll never sail this boat again.
Plus I screwed the battery in via a ali bracket and I'll have to drill a hole in the deck to get a screwdriver at the screws that hold this bracket in. [I guess vecro was invented in 1994?]