DC Electrical Problems

At the end of last year I discovered my wet cell batteries were no longer wet. Over the winter I tried to resusitate them and was marginally successful with 2 of them; I replaced the 3rd. This spring I also noticed the charger (Lewco 20-amp) was boiling the electrolyte even on the lowest setting. After a 5 hour sail last Saturday using the stereo, normal instruments and the autopilot, the engine failed to start with the main battery bank containing the 2 questionable batteries. I jump started the engine with the one good battery (new this spring, part of my fail safe plan). After that I noticed the alternator was only putting out 12.5 - 12.7 v.
The questions I have are:
1) Does the Lewco charger need to be replaced? What is the best onboard charger for a reasonable price?
2) Would a couple of very low batteries cause an alternator output reading of 12.5 - 12.7 v or should the alternator always be in the high 13 to low 14v range regardless of battery condition?
3) What are the best options/sources for repairing or replacing the alternator if I need to go that route? I don't think I want to cough up the $$ to buy a Balmar.

Ther is no special equipment on the boat other than radar which is very rarely turned on and no refrig. Thanks!

Brian,

I replaced my alternator with a marine grade Leece-Neville (Prestolite) 90 amp unit on my Universal M 25. I am happy with it so far & it seems to work well, but I still need to add a battery monitor so I can evaluate it better. That is not # 1 on my list of to-do's, however. There is another thread about that conversion and Maine Sail has a nice web site write up of the conversion done in a Catalina. It cost about $170.....only a fraction of a Balmar.

You could also have your existing alt rebuilt fairly inexpensively.

Brian - To answer your question, yes, bad batteries can bring down the alternator voltage. You can test it by disconnecting the bad batteries and connecting the good one. If you are worried about the alternator you can take it to an auto electric shop and they will test it for you under load for not a whole lot of money. If it is bad they can repair it for you.

For your circumstances I would not recommend a larger alternator. Also, you do not need isolators, combiners, Echo chargers, etc. They are just that much more hair in the scuppers for you.

I would recommend junking the Lewco and replacing it with a three step charger. These will never boil your batteries. Last year did just that for my son on his E-32.

My recommendation is a Xantrex Truecharge 20+ which will charge all three batteries without your having to play with your battery switch(es). They cost $245 at Defender, and may be available for less elsewhere on the net.

There is a ten amp model (Truecharge 10TB) available for $116 that will charge two batteries It will take longer to charge your batteries which may not be a problem for you.

On my previous boat without refrigeration I did very well without any AC charger. I just powered a little more when I left the dock or the anchorage.