[C320-list] Removing 4D batteries from the C320

[Troy Dunn via C320-list]

Hunt-

Decoupling your post from the other thread.

Wanted to make sure you got an answer to that first question which to me
sounded like, "how the heck do you get these things off the boat".

Like most good boat project answers, the answer to your question is "it
depends".

First I would check to see if there are two straps at each end of the
battery, there should be. If there are two straps then proceed to next
part. If there aren't you probably will need to figure out how to rig a
strap out of webbing loops and get them looped under the battery, tied
together across the top so they can't slip apart and then proceed. I had
end straps on mine so I didn't have this issue to unravel.

Do you have a friend. If yes, proceed, if not...get one, if you
can't...can you void the purchase of your boat? Just kidding...kinda...
unless you are incredibly strong...getting the batteries out of the trays
isn't a 1 person project.

So assuming you have a friend. Remove the salon table and set it out of
the way. The next step is to cut a 2x4 so it will slide under the straps
of the 4D battery. Now with the help of your new best friend...you can
lift said battery out of the battery tray. Set it on the floor (towels
are good for protecting the floor, plus added bonus, you can slide the
battery to the galley). Take a breather and plan your strategy for how
you will get the battery one step at a time up the companion way and out
into the cockpit. Similarly you'll want to strategize how you move the
battery out of the cockpit and position it for getting off the boat and on
to the dock. If you are on a floating dock you probably won't struggle too
much to get it off the boat. If you are on a fixed dock, maybe a tad more
exciting.

You will exchange the battery for new battery. Or batteries (it counts as
two batteries if you go for a smaller form factor battery).

Rinse and repeat with battery 2.

Enjoy your favorite cold refreshment with your new best fiend (you are
clearly paying for this activity) Remind new best friend that getting the
batteries out of the boat was the hardest part, but you kinda would love
some help for getting new (hopefully not 4D) batteries on the boat.

Good luck-

Troy Dunn
Hull #514
S/V Wonky Dog
Rock Hall, MD

[jicchak--- via C320-list]

I had to remove 4D batteries from my boat. As mentioned it normally takes two people to lift them from the starboard locker.  After the first step, I removed the companionway stairs to get them out of the way and attached a 4:1 block and tackle line to the boom midway so it lined up with the companionway hatch. You should have a topping lift holding the boom as the vang will not be strong enough. Using the mechanical advantage, the 160 lb battery now feels as if you’re lifting 40 lbs. For what it’s worth, this worked great. 


Sent from the all new AOL app for iOS

[Mark Seyler via C320-list]

If you don’t have a friend available to help lift the battery out from under the settee, you can do it by yourself with a 4-part block and tackle, a 2x4 and a snatch block. The 2x4 needs to be long enough to bridge across the cabin from the shelf above the settee on the port side to the shelf above the settee on the starboard side. Hang a 4-part block and tackle from the 2x4, tie a loop of line through the handles on the battery and attach it to the bottom block. Once you get the battery above the level of the settee, slide the wooden cover back in place under the battery, and lower it onto the settee. Slide it to the aft end of the settee, and then lower it to the floor. If necessary, move the 2x4 aft and use the block and tackle to lower it.
Move the block and tackle to the boom and use it to lift the battery to sit on the cabin top beside the companionway.
I have a fixed finger pier to port of my slip. I have tied a snatch block to one of the pilings on the finger pier and run a line from the cockpit through the snatch block, and back to the battery. I attach a halyard to the battery and use the halyard winch to raise it above the lifelines. Pulling the line in the snatch block while easing the halyard allowed me to pull the battery over the finger pier, and lower the battery onto the finger pier.
From there I put it on a hand truck and rolled it to my car.

Mark Seyler
Sent from my iPhone

> On May 27, 2026, at 8:41 PM, jicchak--- via C320-list <c320...@lists.catalina320.com> wrote:
>
> I had to remove 4D batteries from my boat. As mentioned it normally takes two people to lift them from the starboard locker. After the first step, I removed the companionway stairs to get them out of the way and attached a 4:1 block and tackle line to the boom midway so it lined up with the companionway hatch. You should have a topping lift holding the boom as the vang will not be strong enough. Using the mechanical advantage, the 160 lb battery now feels as if you’re lifting 40 lbs. For what it’s worth, this worked great.

[Rich Allen via C320-list]

Hi Everyone,

I replaced both 4D flooded batteries with 4D-AGM batteries two years ago.
There have been several threads with thoughts about what is the best
battery solution for our boats, and this really comes down to the details
of how you use your boat and maintain charge on your batteries - no single
perfect answer here. However, when it is time to get these batteries on
and off the boat, I wanted to offer the method I used very successfully.

To get the batteries out from under the bench, I used the
technique reported by several others with rope and 2x4 over the locker.
Not much new to add to the other suggestions on this part of the effort.

Getting the battery off the boat, I used a technique which worked well and
I do not think this has been reported by others yet. For my situation, the
finger peer next to the boat is short, and it would be dangerous to think
about moving the battery over the lifeline adjacent to the shrouds.
Instead the front hatch was fully opened by removing the strut which limits
how far it can lift. It was tied off in a vertical position. The battery
was moved to the floor under this hatch by putting it on a small rug and
then dragging it into position directly under the hatch. I used a
spinnaker halyard to hoist the battery straight up through the hatch with
one person grinding using the one-way clutches and several wraps around the
winch, while a person on the deck guided the battery through the opening.
Once it cleared the hatch I was able to guide the battery to the foredeck
area, then over the bow pulpit and onto the dock directly in front of the
bow. The halyard carried the weight, and another control line was used to
pull it forward, while a third person stood on the foredeck to help guide
it. Then a hand cart was used to get it to the trunk of the car. The
halyard is high enough over the deck that it was easy to swing the battery
forward this distance. The same process was used to move the new AGM
batteries from the dock to the forward cabin. I weighed the new AGM
batteries at 120 pounds - others reported 160, either number is a
backbreaker!

I considered using the technique used to remove and reinstall the
Westerbeke 30B engine when we had that rebuilt. For that we used the gin
pole in the service slip at our club, and was able to lift it out the
companionway opening with the stairs removed, and then swing it over the
bed of a pickup truck. I think this would be the safest way, but at the
time I replaced the batteries the service slip was in high demand.

Whatever method is selected, hope it goes well!

Rich Allen
SV Destiny, 1995 Hull #265

[Hunt Bartine via C320-list]

Thanks ALL!  Was going to try on my own but was wondering. Def will be trying to get some help.-hGynnie Anne, '97 North East, Md.
 Hunt Bartine | 21 Southridge | Kennett, PA 19348215-630-7471 mobile
"WORK HARD, STAY HUMBLE,  BE THANKFUL"