Cleaning Up Damage Caused By Leaking Batteries

Now the projects begin…  My plan was to start by removing the plumbing and through hulls, but after 24 hours of charging the house bank of batteries measure 10.8 volts and the starter battery 12.8 volts. ON Pilgrim all the batteries were located under the starboard quarter berth.  I am unsure if this was the factory set up or a change made by previous owners.  The two house bank were strapped down in plastic boxes.  The starter battery was simply strapped to the locker floor.

Pilgrims'Quaterberth Battery Locker

Replacing Pilgrim’s batteries with the 1 year old AGM batteries aboard C’est la Vie is on the project list, but not where I intended to start.  Concern that the flooded batteries have frozen and leaked, elevates this project to the top of the priority list. 

Removing the batteries confirms my fears.  The shelving below and the wall adjacent to the batteries have suffered from exposure to battery acid.  Paint is peeling away.  The wood is soft and disintegrates under minimal force.  Fortunately fiberglass hulls do not suffer damage from battery acid.  I shudder imagining the damage a leaking battery would do to a wooden or metal vessel. 

All that remains of the plywood shelf is the fiberglass tabbing.  The damaged wood is in the battery box in upper left.

Anticipating battery acid, I don rubber gloves.   Soon it becomes obvious that the damage is from a past spill.  The acid is no longer present, but the damage remains.

Using a small grinder with a cut off wheel, I cut away the shelf tabbing from the hull  and follow up with a 30 grit disc to clear away the sharp edges.

The lower edge of the wall between the locker and the engine room also suffered damage.  I probe the extent of the damage by drilling 3/16 holes in the plywood wall.  Starting forward at hull level and working upward, I drill holes at 1” intervals  until striking solid wood.  I then drill holes laterally progressing towards the stern.  These test holes reveal the extent of the damage.  Cutting away the damaged area with a jigsaw and a hand saw, I use the outermost holes as a guide.  Once all the damaged material was gone.  I wash and rinsed the entire area twice - once with a baking soda and water solution followed by a TSP and water Solution. 

The hull inside the locker removal and washing.

And...

The portion of the wall cut away after washing.

The next step will be to cut new plywood sections for the wall and the locker.