New owner-Batteries going Dead

[Footloose]

Bought hull 608 about 2 months ago.  I have replaced the batteries as the ones in the boat were six years old.  I thought that there might be a short in the system but after going through things last night, I don't believe so.  The electrical system is stock and I have order the wiring harness upgrade and connectors.  I don't have any battery busters on the boat, fridge or radar, so I am wondering if the stock alternator will suffice.  We like to cruise on weekends and a week once or twice a summer.  I am on Lake Champlain Vermont.  Will the upgrade help or eliminate my problem?  From the appearance of the cannectors there look to be plenty of opportunity for voltage loss.  I am also looking at replacing the panel this winter.  Any help would be appreciated.

[SteveLyle]

Dave - Welcome Aboard!

It's not clear to me what your problem is.  Replacing batteries after 6 years isn't all that unusual.

There's a wealth of information on this site regarding electrical systems.  Lots of good articles in the Tech Notes section as well - I highly recommend joining the Association so you'll have access to that info - 15 or more years of Tech Notes is really valuable.

The question isn't really if the stock alternator is sufficient - it's what electrical system overall is necessary for your needs.  Battery banks size, technology, and other charging sources come into play, as well as how long you want to go between charging.

With no major power requirements on board, the stock alternator, a couple of 27's as a house bank (about 200 amp-hours total) and a 24 as a starting battery should be more than enough.   Get a 3-stage charger and charge off shore power periodically - if your batteries get low the stock alternator will take forever to top them up - it's just not designed for that, and doesn't have a 3-stage voltage regulator, so it's limited in what it can do.

Starting with the harness upgrade is a good first step - it will ensure that you get the most out of your alternator (vs the voltage drop you get with the long run to the panel and back).

Steve

[Stu Jackson]

Dave, Welcome

In addition to Steve's points, I recommend that you do an energy budget.  Even with no fridge, with your low draw, you'll be able to figure out how long you can stay out without recharging, and how much your alternator puts back in (it's not much).  

Also read Jim Moe's electrical design on the Projects page of the main website.  He explains the C34 electrical systems very well.  Unless you're an experienced boater who understands boat electrical systems, I wouldn't rush into anything yet, just learn how you intend to use the boat, and learn more about electrical systems so you can make an informed decision.  

As Steve notes, there's lots on this message board.  If you do searches on "batteries," "electrical systems," "alternators,", etc. you'll find a lot.  Also check the Tech Notes index to see what's been published.  

When you join the Association you also gt a FREE CD-ROM with the Tech Notes, Projects and FAQs up to 2001!  Suggest you do the solenoid installation (in either Projects or FAQs on the main website) when you do your wiring harness.  Also check the fuse between the start switch and the starter.  

Find Steve's First Year Weblog here, it's great reading. Do a search on "weblog."

Please note that the FAQs on the main website are actually about C34 boating issues, not about how to use the website, like many FAQs usually appear to be.

When we bought our boat in 1998, all I remember is doing a LOT of reading, in addition to sailing, of course.  It sure helped, and since then there's tons more information available here.

From a bit I wrote about our 2004 cruise (10 days): [applies more to those with higher electrical loads]

Helpful Hints:  Electrical Systems:  For extended cruises for those with OEM stock alternators and no external regulation, there is inherently a steadily diminishing law of return in battery charging even if you motor a lot everyday.  If you do an energy budget, even if you motor for eight hours a day, you will be drawing down your batteries, regardless of how much you've increased your house bank.  You WILL need to stop and plug in every week or so.  Do the math.  If you really want to stay out "forever," add solar and a new high(er) output alternator and smart regulator.  We minimized use of electric lights with our lamp oil trawler cabin light and lamp oil anchor light hooked onto our Garhauer dinghy davit, but most of the energy use is from the fridge.  With our large 315 amp hour house battery bank and a separate start battery, we were very comfortable being out in two different situations.  The first was for a few days without motoring or plugging in.  We turned off the fridge at night, so we only used 30 to 40 amp hours a day and could go three or four days without running the engine.  The second was knowing we'd be motoring for at least five hours or plugging in at a marina (even for a few hours with a good charger, or overnight).  So, before you go, make sure your electrical system is up to snuff, and that YOU understand it, so you can really relax and enjoy the peace and quiet without having to worry about your boat systems.

[Footloose]

I guess I should have been more sprcific.  The batteries are going dead after replacement.  Our boat swings on a mooring so we don't get to charge from an external source very often.  It sounds as though I should get a different alternator sooner than later.

[Stu Jackson]

Dave, before you get a new alternator, get a solar panel.  Think about it.  Unless you're completely charged from the alternator (which won't happen if you're actually sailing!) then the batteries will self discharge (unless you bought gels or AGMs).  So you come back to a boat with a ?ble battery charge and can't start your engine!  An 11 watt solar panel will keep your batteries up.  Any solar panel larger than 11 watts will require a regulator.  Start by connecting them to your house bank directly and use the house bank to start, the alternator will charge your start (backup) bank while motoring.  It's one of many ways to do it, but we never leave our boat plugged in even though we have shorepower.  You'll read about this as you get into the board.

Given my post about the steadily diminishing law of return (which you just proved!), and the self discharge of wet cells, consider simply tying up to a dock with power for an hour or two if you have a good shorepower charger.  Do a search on "solar" and "chargers", too.

You do have choices.  I'd also recommend tracing the wiring in your boat to understand how it works before you do anything.

[Paul Bosquet]

Dave
I too am on Lake Champlain at Snug Harbor and often go to Mallets Bay. I had most of my electrical redone , Batteries 4  x 6volts, alternator 100 amps.  There was a refit published by Jim Moe who had put together a real nice upgrade for me and it has worked real well. Would be happy to show the you the work done on my boat.

Paul Bousquet

Eliosso
C34 986

[Ron Hill]

Dave : As Stu said get a solar panel and keep your batteries topped off.  You might also check to see if you have any current draw when everything is shut off.  

If you don't have any of the hi drawing items onboard (fridge etc) and can motor 1 to 2 hrs/day and plug in every 3 or 4 days when you're cruising; I'd guess that you stick with what you've got.

You might consider installing a battery monitor.  It will give you the health of your batteries, the # of amps you consume and then you can decide if a hi-output alternator is necessary to sustain the batteries for your type of cruising.  

[Stu Jackson]

Paul

The referenced Jim Moe article in my earlier post IS the one you referenced and is NOW thanks to Mark Elkin on our Project page at

http://www.c34ia.org/projects/projects-electrical-system-upgrade-2.html

Thanks for getting Jim to continue to pursue the article and I had fun working with him to edit and complete it.    We're still trying to get Mainsheet magazine to publish it, but YOU SAW IT HERE FIRST!!!

Please also see John Gardner's very helpful electrical article also on Projects.

LOOK AT THE MAIN WEBSITE, TOO, LOTS OF GOOD INFO THERE.

Thanks guys!