Considering A Battery Upgrade? Factor In The Change In Weight

Version 2

By Rich

Our 1989 Sabre 42 originally came with 3 Group 27 marine batteries weighing +/- 67 pounds each for a total of 200 pounds or so. They provided 180 amp hours of house capacity (from two batteries) or 270 total if you factor in the third engine battery as well (I am assuming one of the three was originally dedicated to the engine). A prior owner upgraded our boat to one Group 27 engine battery and two 4D House batteries. The upgrade was well meaning, bumping the dedicated house battery capacity to 420 amp hours while still reserving a dedicated Group 27 for the engine. The downside was that the upgrade increased the total battery weight from 200 pounds to 331.

The increase in weight has had two implications for our boat. One is that the new batteries have teamed up with other starboard-side equipment upgrades to put Le Saberage slightly out of trim, dressing mildly (but annoyingly) right when at the mooring. Per Sabre’s recommendation I plan to install lead counter weights on the port side of the boat to compensate (more on this project later). Unfortunately, the second issue is more serious: the installers failed to verify that the sail locker floor was strong enough to support the extra weight. It wasn’t. The flooring has broken loose in parts and begun sagging toward the bilge.

Today I got a start on the repair, which began with the need to remove the batteries from the depth of the sail locker using only my modest physique and a little ingenuity. The engine battery was light enough to be hefted out using pure will power, but each of the two 130-pound 4Ds required a bit more creativity. As shown below, the process began with removal of the sail locker lid. Next, a spare block & tackle was lashed to the boom and a few guide lines helped coax the batteries out of the locker without gouging everything in sight.



Once each battery was rested on the cockpit floor, the block and tackle mount point was moved to a point just above the companionway.




Now I had access to the failed flooring to get a better look at the damage. Note the scum line at the left in both photos; this was originally the level of the floor before it began to fall away.



With the batteries’ section of the flooring removed, I could see the issue: the cleats used to support both sides of the flooring were insufficient to support the new load. After getting these cleats back into position I will glass in supports from underneath.



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