Betteries for Mexico

[Sanders]

I am in a serious discussion with a good marine electrician, and friends who have sailed in Mexico, about replacing my batteries and enlarging the bank for cruising in Mexico.Electrician recommends AGM or wet cell, lots of them, relocated, as more efficient.Friends warn that Mexican marinas and chandleries can support only wet cell batteries for replacements, and if you have one battery die you'll be up an expensive creek.He says that you go with what the locale can support, or you can find yourself flying back to the U.S. and figuring out how to pay duty on expensive items for replacements.Anyone had experience with this in Mexico? Have you been able to find replacements or support?Anyone want to chip in one relative merits of different battery types for cruising specifically in Mexico?FYI the electrician's recommendations would cost about four times what wet cell batteries would cost -- over a thousand dollar before I'm done, and he says they should be supported by a new alternator and digital regulator. = More boat bucks.I'd appreciateyour input.Sanderss/v Good News

 

[Benny]

Excellent advise.

If you are going to be cruising extensively in Mexico and other Central American countries go with what the local markets support. I'm sure you can find AGM replacements in major metropolitan centers but according to Murphy's Law your battery will fry up in a remote fishing village.

 

[John Brecher]

My personal opinion

1) If you were realy in a tight corner an automobile battery would save the day. As long as it will crank the engine reliably and you recognize it is not permanent.2) If you stay abreast of the maintenance, which mainly means making sure the batteries stay topped up with good water (steam distilled) and are clean then wet cells are O.K. They are also pretty immune to over charging, as long as you tend to the water level. (Excessive water use is indicative of over charging). Total cost of ownership will be less.3) If you do go with wet cells bear in mind that they can damage other stuff from spillage, put them in battery boxes and keep sails, cushions etc away from them. Wear eye protection whenever you work with them. Clean up very carefully after taking the caps off.4) Know that a 3qm30 can be started with a weak battery by decompressing, cranking and then restoring compression once it is rotating.John Brecher

 

[BobW]

Lots and lots of variables....

I don't have any real answers for you, Sanders, but perhaps a few questions will help you think through the issues:1. Do your batteries/charger/regulator/alternator NEED replacing?As you pointed out, that's a big investment in boat bucks, of which there is never an unlimited supply (simply because those who have a bottomless bucket of money aren't 'cruisers'). If you don't have a real need for new power stuff, there are probably other items higher on the list (tempurpedic mattress toppers? A new genoa?)2. Have you calculated your real power needs while away from the shore power plug?3. Will you be running the engine anyway, for engine-driven refrigeration?4. Would you power needs be better met by more batteries or by more ways to charge them? Or a combination?5. Presuming you'll have 2 house battery banks and a dedicated starter battery, what effect will losing any 1 of those 3 sources have?If you added 1 AGM 8D in a separate bank, that would give you a lot of extra amps. Losing it wouldn't leave you dead, you could replace it with a wet cell 8D or 2 smaller Group 29s and not have to leave Mexico.Something to consider: if you're away from shore power, overcharging is rarely, if ever, going to be a problem - you'll mostly be worried about getting all the way up to about 90% of capacity, where the charge rate drops off to where running the engine isn't worthwhile and wind/solar supply rarely overwhelms consumption.If you don't have it, I highly recommend Nigel Calder's book: BoatOwners Mechanical and Electrical Manual. It has a LOT of detail. Of course, the one thing I don't remember reading in that book is....... what sort of batteries are best for cruising in Mexico. Isn't planning (and dreaming) half the fun of it? (for those of us who can't go yet, anyway)Cheers,Bob

 

[Sanders]

update

Fellas,Thanks for the good counsel. I looked at several options and currently have a interim plan for the next steps:-- I will glass in stringers high in the center bilge, drop in a shelf and put two (or possibly 3) Gp 27 batteries in that location in boxes. The electrician agreed with the idea of staying with wet cell for travel in Mexico.-- The electrician will connect everything with new cables (the lugs were almost worn through) and install new switches to separate the house and starter batteries. The "battery isolater" was non-functional, and according to the electrician, not that good an idea for my setup.-- When that is done I will retest the alternator/regulator to determine for sure if I have a problem, or not. If the alternator is bad, the electrician will replace it.If we make the decision to go to Mexico, then we will weigh the benefits of adding another bank of two, or solar panels, or a mix.Then we will begin on the other "to do" items...It was a beautiful sunny day at the dock at Alameda (120 miles from my home), despite the frost on the companionway early in the morning. I'll be back in two weeks, go sailing, and start the battery job.Fair winds,Sanders

 

[Seattle Scott]

Hey Sanders

I just saw your post re putting batteries in the bilg. PO did that on my 37C, put in 4 cross wise on an aluminum shelf with cut out to get to the keel bolts. I will try to post some pics in the photo forum this week end, maybe give you some ideas

 

[Ed Schenck]

Mexico?! For how long?

Sanders, how many years are you going to be there? I got eight seasons from my Gel batteries. I have four new AGMs in the basement only because we are finally going cruising. The Gels were still holding a charge last summer. I expect to get at least eight years of maintenance free, never think about it, DC voltage. I did invest in a 3-stage regulator and a modification to my 80-amp alternator just to be safe. These will be house only. I already use a 900CCA AGM for starter.There is a very large difference in bilge size between the shoal draft and full keel boats. Has anyone put group 27 batteries in a shoal draft bilge?

 

[Sanders LaMont]

Ed, who knows

The very tentative plan is to take the boat down to Puerto Vallarta this coming Fall, cruise that area through the winter, and keep it there a) a couple of years, b)till we move down there, c) till we decide to hang it up and put it on the market -- there or here.We dunno. And, not suprisingly, it turns out we have quite a few things that have to be done here first, including some doctor appointments and elective surgery, plus our children and grandchildren have just decided to move near us in the mountains and we are weighing how wise it would be to take off the first year they are close. Plus, my very skilled son-in-law is going to be too busy with his new place to deal with my boat stuff.Regardless, the electrical needs to be addressed soon so we can enjoy the boat without worrying about it. Most of the other stuff (stove, windlass, hot water heater, brightwork) can wait a while.I may opt for a short-term solution.Of course, everything takes longer than it used to, and cost more. Isn't that one of the Proverbs????We'll see what Spring brings. Cheers,Sanderss/v Good News