Our batteries were about three years old and started to get noticeably HOT. Two of the 4D batteries reside underneath the nav station seat and my toosh was getting too toasty!! The third is in the engine room. When we first arrived at the boat in September the water level inside the battery cells was very low. About 16oz of distilled water per cell were needed to bring them up to the proper level, but even after that they were still bubbling over, seeping out of the vents on the top of the batteries. While it’s not straight battery acid that’s coming out, it’s still very corrosive and dangerous. You can see the spillage in the picture above (disregard the terrible quality!)
This was a high priority boat project and we couldn’t put it off any longer. We would have liked to put in 8D batteries to yield more amperage for a longer duration but the housing just wasn’t big enough and it’s not critical enough to rebuild the existing box or expand elsewhere. Our research discouraged us from the higher priced AGM batteries or gel batteries. The increased life just wasn’t enough justification for the higher price, and we’ve also heard from many salty dogs that they don’t always have a longer life either. We don’t mind the additional maintenance of refilling the distilled water every couple of months, especially if it means saving a few hundred dollars on these bad boys. We went with some Deka Lead Acid batteries for $220 each. Plus, we were able to get them from the yard right here at our Marina. The guys even said they would come pick up the old batteries at our slip. What a deal! 
The first step was to shut off all the power. No big deal, it’s just in the high 80’s outside and muggy as all hell. No power means no air conditioning…
Peter put on his safety glasses and gloves, then used a little T-9 to loosen up the terminals and the first one was ready to come out. A whopping 80lbs of battery and seeping lead acid had to be lifted out of that hole without dripping anywhere. Peter and I got it onto a black trash bag, but there was NO WAY I could help him lift it up the vertical 5′ ladder and through our companionway into the cockpit or over the lifelines onto the dock. Our super nice neighbor Karl donated some sweat equity and came to the rescue. 
It’s not a real boat project unless you get sidetracked and start a new one before finishing the first one, right?? Don’t forget, we still have NO POWER and NO A/C since we are only 1/3 done with the batteries. In order for the wood platform to screw back in properly over the top of the new battery, we got the chance to use our handy-dandy vice that was left by the previous owner on the back side of our engine room door. There was a small piece of wood that was beginning to split so we used some liquid nails and a screw to fix’er back up. 
The clock ticks on and we finally get the board back in place. My red toolbox fits perfectly where the previous owner had his toolbox. He laid non-skid strips down with screwed on wood blocking to hold the toolbox in place while underway. There’s also a strap that goes over the top for double measure. The snap that holds the strap also busted off but that’s a little less critical so we’ll add that one to the “list” for another day. On to finishing the batteries…
The last two sit more than snuggly inside the nav station seat and there is a grip of wires in the way making it extra difficult to remove the old leaking batteries. We are running out of daylight. It’s not getting any cooler and we are both sweating all over the place. I am able to lift the first one out of the box with Peter, but not the second one. Karl comes back over to help us out again. Two men are stronger than one! Now we just have to get them hooked back up properly and quickly. The headlamp came out long ago. Good thing we have little batteries to help us shine light on the big ones!!
Before lifting the new batteries in, we need to clean out the box with baking soda and water to neutralize all the spillage. We’re not sure how long it had been like this, but there was an awful lot of corrosion and that’s never a good thing on a boat. Luckily the structural integrity of the box wasn’t affected and we won’t need to rebuild anything… yet. Now totally dark, and still sweating, we tried to air out the fumes from the neutralization as best we could. We were determined to get this finished in one night so I mustered up all the strength and gumby-like leverage I had to help Peter drop them into place one at a time. After all the wires were put back together the right way and the terminals got a fresh coating of T-9, it was time to see if we had juice. Whew!! Everything seemed to be okay.
We were both so tired and on the verge of dehydration that when we plugged the shore power back in to get some air conditioning, we plugged them in the opposite locations. The fault warning was going off and it took us a few minutes to realize it had nothing to do with the connections for the new batteries, but that it could be the shore power cables. Peter went out to switch them and the beeping stopped. Finally! Light and cool air!!! The poor puppies had been waiting so patiently for dinner and potty time. We got the pups outside first, then back for their dinner and then we were finally able to head to the showers to get cleaned up.
The work wasn’t done yet… we still had to neutralize the acid that had leaked out and down onto the carpet. We sprinkled some more baking soda and let it do its work. There was more reaction than we were expecting, but its all cleaned up now. We’ll be tossing that piece of carpet for sure and replacing it very soon. Another thing to add to the list!
All in all, our first major boat project took longer than we anticipated but it was successful in the end. Next time we replace the batteries, it will hopefully take us half the time and we will be sure to start the process on a cool day and early in the morning :)
