Messages

1.   (My assumption being that if I replace the starting battery with something that isn't dual purpose, then I can't use them without discharging the battery enough to damage the battery.)

2.  12V would be easier (no rewiring) but 6V gives me more capacity so that's where I'm headed I think. 

3.  I suppose it would be good to know what percentage of folks actually NEED that additional capacity but my assumption is that I will for weekend trips, or at least that I'll appreciate it.  For this year, who cares, but my hope is that I'll get 5 or more years out of these batteries if I treat them right, and the capacity will be an issue by the end of their life.

4.  As for charger, Maine Sail recommended a Sterling ProCharge Ultra.  That's where I plan to head for the moment.

1.  Not necessarily.  If, for now, all you plan are short day sails, using a cheap starter (auto) battery for short term (a few hours) at low load (simple instruments, VHF on standby/listening, throw in a stereo which uses 2A at max volume) you will not really harm the battery.  You'll be motoring at the beginning and end of those sails anyway.  Forget dual purpose - they do neither well.  Auto Zone batteries are really cheap, really.

2.  Rewiring what (if you don't have anything)?  If you go 6V you'll need the short jumper wires to make 12V anyway, right?

3.  It doesn't matter what anyone else does.  Really.  Since you grasp the concept of the energy budget, consider this:  turn the concept upside down.  Make "use of the available" and "see what it gets you" in terms of longevity at anchor.  For 6V, you have only two choices:  2 or 4 6Vs, for a nominal 225 or 450 ah.  For 12V, using Group 31s, each battery will give you 130 ah, your choice of how many for your house bank (I have 3 for 390 ah).  That's it.  Then back those ahs into how much your energy budget says and you will see how many nights you can last without recharging (or running your engine).  You may also have seen this:  Record of Daily Energy Use of 100 ah per day:  http://c34.org/bbs/index.php/topic,6353.msg41471.html#msg41471  If you have a fridge that's a "normal" use pattern.  KISS.

4.  Thing is, they come in different sizes.  Also included in the "Electrical Systems 101" topic.  Your boat, your choice (for sizing, but 60A is a pretty good choice, smaller takes longer to charge). 

1. Good thought.

2. Maybe nothing.  Part of this weekend's project is to understand what I've got in terms of keeping both banks charged... whether the battery selector selects what gets charged as well as which gets used.

3.  Good thought.

4. Haven't given much thought to size of charger yet.  I'll definitely research.  Not sure that speed to recharge matters to me as I expect I'll leave the boat plugged in.  I expect that most of the time the charger will work it's magic after I drive away from the boat.  I know there is a debate as to whether it's better to unplug when I leave, which would mean that the charger would need to be quick or they'd never see 100%.

Stu:

I hear you and, by and large, that's what I intend to do... install a new starting battery where it sits, make sure the alternator is charging it, and move the boat to the marina.  That allows me to quit paying double (slip plus yard) plus it allows me to day sail.

That said, I'd like to move as quickly as I can, without making misinformed decisions, so that I can start weekending on the boat and using the instruments.  (My assumption being that if I replace the starting battery with something that isn't dual purpose, then I can't use them without discharging the battery enough to damage the battery.)

12V would be easier (no rewiring) but 6V gives me more capacity so that's where I'm headed I think.  I suppose it would be good to know what percentage of folks actually NEED that additional capacity but my assumption is that I will for weekend trips, or at least that I'll appreciate it.  For this year, who cares, but my hope is that I'll get 5 or more years out of these batteries if I treat them right, and the capacity will be an issue by the end of their life.

As for charger, Maine Sail recommended a Sterling ProCharge Ultra.  That's where I plan to head for the moment.

Forever and ever, amen.

Hey Dave.. I wonder if the cover over the compartment is an issue because it's not secured and could, in the event of a knockdown, fall off and expose the batteries?  Far fetched, maybe, but maybe some positive latch of the hatch cover would suffice?

Also, I wonder what it would take in that battery box to make it acid tolerant?

Stu:

I appreciate your thoughtful, and well thought out, comments.  This site, and the wealth of knowledge you guys provide, is worth a fortune!  I'm in the medical device software business, very much driven by regulations and the resulting standards and their interpretations, so I hear what you are saying.  Typically, as in this case, there's not enough info provided to be of much help.  The relevant sections of E-10 are:

10.7.1 Battery mounting materials and surfaces shall withstand electrolyte attack.
10.7.2 Provision shall be made to contain incidental leakage and spillage of electrolyte.

Neither is enough to settle any debates here, or even answer any simple question!

I'll definitely study what's been written here.  I'm impressed with both the solutions that you guys have come up with and the time that you've spent documenting them for the benefit of folks like me.

Re Maine Sail, I did a paid consult with him last week and will probably both do another and purchase my parts from him as I go.  Fantastic resource and recommendation.

My preference would be to learn my boat over the season prior to making changes.  Unfortunately, my charger is fried and my starting and house batteries area all fried, so I have to move quicker than that.  I think I could install a new starting battery in the battery box, use only the alternator to charge it, and move the boat to the marina from the boatyard without any issue but I'll need to move on house batteries quickly and, without a charger, they aren't worth much.

Anyway, I'll absorb every word and no doubt ask more questions before I do anything at all!

Noah:

My reading of other's interpretations of the standard is that you are 100% correct, with the possible exception of potentially needing to make the inside of the box itself acid tolerant.  That said, I have no idea what that would take or whether it's even required.  I figure reading the standard and forming my own (mis?)interpretation is the next step.  All that said, I'm heading the same direction you went.

Mike

There's so much about my boat that doesn't meet current ABYC standards that I'm sure what I do will be an improvement.  That said, I want to use my dollars wisely and improve the value of my boat, not make expensive mistakes.

I just forked over the $185 to join ABYC for a year so I could study the standards.  I'll report back if anyone is interested.  E-10 and E-11 seem the relevant ones to this topic.

Thanks a million, folks!

Thanks all!

I find myself with a toasted charger and a battery bank that needs replacing.  Reading the upgrade thread has me dreaming of the increased capacity of the Trojan T105's but I'd love to see photos, if anyone has them, of the 4 batteries mounted in the battery compartment that resembles mine... I'm guessing any Mk1 would have the same battery box as my 1.5, but who knows?

I'd also love to see photos of an alternately mounted starting battery if anyone has anything.

Got two... Give me your mailing address. ;)

Here's my lack of bump photos...

My boat doesn't have the internal bumps but I can't seem to post pictures... I've tried including them as attachments and see them uploading... but the post never shows up.  Can someone educate me?

As for the PVC T's and such, I'm getting rid of mine at the same time.  The valves I'm most considering now are the Forespar OEM Series 93's.  They may be the same that CD sells, but I can't be sure since they'll only tentatively confirm that they are forespar at all.  I know the series 93's are much newer and stronger than the previous generation which came after my boat was built. 

Anyway, they come in a wide variety of configurations... I'm hoping enough that I can have nothing but the valve and parts it came with plus the hose.

I was pretty impressed with MaineSail's destruction test of the thing!

http://www.forespar.com/OEM-Valves.shtml

Paralysis by analysis... maybe I'll just sit this season out and sail next year!