When I purchased my boat in 9/12, the starting battery was completely discharged. So this winter, my boat yard pulled all the batteries out to load test them, and reported that they were not holding a charge. They recommended replacement.
House: 2 house batteries: Group 31 Gel Batteries
Starting: 1 Optima Redtop Starting Battery
According the the PO's maintenance log, these batteries were originally installed in 9/09 and so are only 3 years old. Moreover, the log says these batteries were installed to replace identical batteries that had been installed in 8/02. So, the first set went for 7 years.
Is the 3-year life of the existing batteries unreasonably short? Could the yard be wrong? Does this indicate that something in the charging system might need to be addressed? (For the last few years the PO only really day sailed the boat and kept it plugged in at his dock.)
Also, the price for the new batteries being quoted by the yard seems low. For example, they want $254 for a new G31 battery which is lower than I see at Defender, WM, etc. I don't mind paying less
, but is there something I need to check to ensure the replacement is a quality battery?