Marine Battery Question?

Question

Today i bought a 65lb power drive, electirc turning, 58 inch shaft trolling motor...great deal from craigslist.com. It came with two 12v batteries. however the guy who had them left them sitting on his garage floor, all the cells are still we but low on fluid..will the batteries take charge and stay charged and if so.. should i put sulfuric acid back in them or just use distilled water? the Trolling motor is 24v so i need both batteries.

thanks guys and gals

Answer 1

It is normally appropriate to add only distilled or demineralized water to a battery.  The exception would be if some of the electrolyte was lost (such as in transit); if you add water, and charge the battery, and then check the acid concentration with a hydrometer, you can tell whether the acid is correct.  

Answer 2

Use the water and a deep cycle charger, the batteries on the floor pulling down the charge is a myth. the low fluid looks bad, they may have been left on a charger way to long, this can kill all types of batteries.

Answer 3

being low on water and in a discharged state for awhile will cause sulfation (sulfur crystals form on the plates) and reduce their amp hour capacity.

water evaporates, but sulphuric acid does not -- just add distilled water (minerals in tap water contaminate the plates and interfere with recharging).

don't forget a 24V 40-amp circuit breaker -- if (when) ya get a bit of fishing line on the prop shaft, don't want to burn it up.