Battery Chargers?

[Maynard Rupp]

Our 1986 36C Hatteras has the original battery charger. It is a Pro Mariner 20/35. Our batteries seem to use some water and last only about 2 years. Having said that, we do leave the boat plugged in at the dock and the battery charger on when we are not running. I keep hearing about "modern" chargers. What is the advantage? We have no need for an inverter, so just keeping those 2 8D batteries fresh longer is all we need.

 

[Pascal]

jst put a wall timer on your charger, to run it 8 hours a day. that will reduce water consumption by at least half. i get 4 to 5 years out of my cheap exide golf cart batteries (4 x 8v)

cheaper than replacing the charger, if you do, modern charger are 3 stage and easier on the batteries.

 

[REBrueckner]

My Statpower 40 "smart" chargers shut off if there is no drain over a specified period of time from the batteries..that is, no appliances drawing current....supposedly the three stage charging is faster but not detrimental to battery life...but I found switching from an old ferroresonant to smart chargers did NOT extend my typical five year battery life.

If you are getting only 2 years from batteries something is wrong.

If you run your batteries way down past 50% capacity just a few times a year that will dramatically shorten their life...as will not promptly recharging them when discharged... so your post doesn't really provide enough information to make an informed suggestion....
your short life battery life may well have nothing to do with your charger unless it is operating improperly....if you need to add around a cup or two of water per 8D cell each year for moderate battery use....and your batteries get up to about full charge via hydrometer....and it shuts down to close to zero amps without appliances running.....likely your charger is ok....