Add a little electrolyte, but don't overload it- - - -a couple of ounces per cell should be about tops. Once the sulfate crystals start to redissolve, you'll end up with acid that's too strong if you disturb the chemical balance. "Full charge" specific gravity on an open cell battery should be around 1.265. Anywhere above a 1.250 specific gravity reading (on all the cells) is sufficient to do a high rate discharge test. A battery hydrometer to check the concentration of the acid is pretty much a "must have" tool when charging and testing open cell batteries. You don't have that option with a saealed top battery. A "discharged" battery will have an electrolyte specific gravity of 1.000- - - - -plain water. All the sulfuric acid has been absorbed by the cell plates.

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Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!