Our Ericson 34 has two house batteries and a separate isolated starter battery. The starter battery is relatively new -3yrs old top of the line 27 series - and she would not start the diesel last week unless plugged in to shore power. She showed 12.32 volts, terminals were clean, cables were clean, but no oomph. When I looked inside the battery, the electrolyte was darn near all gone. Yikes, how can this happen?
The electrical specialist at the marina suggested the following scenario - and it made a lot of sense. I would sure appreciate some thoughts on how accurate this is.
When cruising, we tend to really draw down the house batteries, nav gear, laptop, VHF, fridge for a couple of hours each day, cabin lights, and when cold outside, good old Mr. Espar, and finally the anchor windlass. While at anchor we charge the batteries by running the diesel for 30 minutes twice a day. She has a 50 amp alternator. If at a Marina, we plug into shore powere and the charger takes over. It is the charging that boils off the electrolyte in the starter battery. The house batteries are seriously depleted and the alternator sends full 50 amp charge to them - yet the starter battery is probably still fully charged, but getting massive charging from the alternator, or the shore power charger. I was told that while the house batteries are charging, the starter battery is merrily boiling away electrolyte.
If that is indeed the case, we need to change our wiring and put some safeguards in place. Can anyone make suggestions?
Thanks in advance.
Tor
The electrical specialist at the marina suggested the following scenario - and it made a lot of sense. I would sure appreciate some thoughts on how accurate this is.
When cruising, we tend to really draw down the house batteries, nav gear, laptop, VHF, fridge for a couple of hours each day, cabin lights, and when cold outside, good old Mr. Espar, and finally the anchor windlass. While at anchor we charge the batteries by running the diesel for 30 minutes twice a day. She has a 50 amp alternator. If at a Marina, we plug into shore powere and the charger takes over. It is the charging that boils off the electrolyte in the starter battery. The house batteries are seriously depleted and the alternator sends full 50 amp charge to them - yet the starter battery is probably still fully charged, but getting massive charging from the alternator, or the shore power charger. I was told that while the house batteries are charging, the starter battery is merrily boiling away electrolyte.
If that is indeed the case, we need to change our wiring and put some safeguards in place. Can anyone make suggestions?
Thanks in advance.
Tor