[Amel Yacht Owners] Lifeline AGM 105 AmpHr Battery Replacement Procedures
Bill,toggle quoted messageShow quoted text
The only thing that I can think of to add would be to insure that the new batteries were individually all at a similar state of charge before connecting them. It might also be a good idea to do a load test on each individual battery before connecting them together to ensure that they all seem healthy. Most auto parts stores have a load tester if you do not have one yourself. I am sure that one of the battery experts on the forum will step in to help you further. Best of luck.
Your plan looks sound. I replaced the 12 batteries in my SM2k last year and followed a similar procedure. I agree with James that it would be best to load test each battery before installing them to make sure they are all good batteries. People have reported getting "bad" new batteries. Ideally, this would be done BEFORE they are shipped out to you. If you cannot get a real load test done, get your hands on something like this: https://www.amazon.com/BA7-100-1200-Electronic-Battery-System/dp/B0015PI7A4 Bill Rouse (ex BeBe) recommended this device to me and I'm quite happy with it. When I replaced my batteries I had the battery shop load test each battery in my presence using their real load tester and then I used my BA7. It was within a few % points of the "real" load tester.
I have taken your plan, put it into numbered steps and added a few suggestion below in RED:
1. Take several pictures of the existing battery installation for reference.
2. Use masking tape to label each battery with a number and each cable (at both ends) with the number of the battery to which it is attached including whether it's the plus or minus terminal.
3. Take several pictures including one of each "pair" of the labeled installation and make a diagram on paper.
4. Turn off all power to the boat including the Permanent +12v for the radio (assuming you have this).
5. Disconnect the batteries with the big red handles in the pilot berth.
6. Remove the batteries, inspect each cable and their terminals for corrosion, looseness etc and repair as required.
7. Clean all the battery cable terminals with sandpaper.
8. Replace all 8 batteries in place and reconnect all the cables using the photos and diagram as a reference.
9. Use come Corrosion X on each of the battery terminal before replacing the plastic caps.
10. Ask the boss to check that everything is correctly connected per the diagram and pictures. Lucky for me my boss is an Electric Power Engineer!
11. Use a multimeter to confirm that each of the four pairs of batteries is indeed 24 volts (assuming you have an SM and your batteries are wired in +24v series/parallel configuration)
12. Close the red battery handles and restore boat power.
13. If all is OK, turn on the battery charger and fully charge the batteries.
14. Check that the vent line is clear.
SM #440 Cara
Deale, MD USA