Battery replacement

[Dirko]

Optima are AGM type batteries. Make sure you have the proper charging system, it's different that wet batteries.

I can attest to the need to charge the AGMs correctly. I had an AGM mixed with a regular wet battery - ended up frying the flooded battery; replaced it with another spiral AGM, and ended up frying both. Broke both the don't mix battery types (PO) and dont't mix old with new rules.

I'm not sure if my charging method was the culprit, or if the setup I have was the root of the problem. I have a battery directly hooked to the motor (don't need the battery selector on position 1, 2 or both to start - however always start with the selector on 1). I would hook up my solar panels to the 12v plug and switch to either 1 or 2 depending on which battery had the lower voltage.

This year I put in a couple of deep cycle marine batteries - good old Canadian Tire replaced both AGMs on warranty. I bought a cheap regulator (Coleman charge controller) that I was going to put in-line with the solar panels, as I assumed I was overcharging the batteries. When I started tracing the wiring I found a ProMariner ProSport charger wired in. Looking through the documentation, it looks like it only regulates shore power.

I ended up setting the selector to 1 and charging the cranking battery when leaving the marina under motor power, and setting to both and effectively charging the house battery, when returning. It's been working so far, but the voltage often drops below 12 on either of the batteries depending on use and time between charges. I'm nervous that even the deep cycle batteries would fare better if I kept them charged over 12.5 volts, but don't want to fry them with the solar panels again.

[innervations]

I have been doing a fair bit of research and Ctek seem to be excellent though a little pricey chargers that will handle both AC and solar panel input. It is not just the cost of ruining batteries but the hassle when you are out on the water and your fridge won't run or I have to use the auxiliary power pack to start the outboard.

[Dirko]

Good point on the price. Cheap vs. new batteries every year - thanks I'll look into one.

[Dimitri-2000X-Tampa]

Hmm, it looks like battery discussions are about as controversial and filled with misinformation as discussions about lightning strikes. And in my case, the two are related. I stopped buying expensive batteries a long time ago after figuring out that the cheap walmart Everstart batteries are actually better. About 2.3 years ago, I had a lightning strike and normally I do all mechanical work myself, but I was so overwhelmed with broken stuff both in the boat and the house that I hired a yacht repair mechanic to come do the majority of the insurance claim fixing work on the boat. At the time, my walmart batteries were a couple years old and still performing flawlessly. I was in the habit of using one group 27 deep cycle and one group 24 starting battery since I don't run a fridge or anything super power hungry, i typically just run on the deep cycle and keep the starting battery as a hot spare.

I got home from work one day and the mechanic had swapped both of my batteries out already (without my permission)...saying that he had already authorized the insurance company to pay for them because "sometimes" a lightning strike can cause batteries to fail shortly afterwards. At the time, they were working fine, but I didn't know any better one way or another so I figured if the insurance company was paying for them, then what the heck, I'll just get some new batteries. Well, the mechanic also seemed to be of the opinion of most people in this thread that deep cycle are better on boats than starting batteries so he replaced both the group 24 and group27 with DC batteries. And, he installed two West Marine batteries.

Now I don't usually like to bash companies publicly and I don't know who makes WM batteries, but those things are crap that cost close to twice as much as the Wallymart batteries. I could tell right when they were new that they were taking too many amps when fully charged. I could never get them to suck less than 2 amps right when they were brand new, and by the time they were a couple years old, that climbed to closer to 3. Over this last summer, there were a couple occasions that the battery seemed a bit weak when starting the motor. The starter would turn a bit, stop, then turn some more. I'm thinking, these are crap batteries. And sure enough, about a week ago, I haven't run the motor in a few weeks, so I dip it in the water and try to turn the motor with the supposedly fully charged battery and it won't turn it fast enough to start. So, I switch to the other battery and try it and it does the exact same thing. I could only start the engine by having BOTH batteries selected in parallel.

My cruising season is about to start soon and I don't want to go for long trips with crap batteries so I went to Walmart and bought two brand new ones. I accidentally bought a group 29 with 845 CCA for some reason, but when I looked at my battery box, it looked like a group 29 would fit in there..so, after shoehorning it with a screwdriver, it actually dropped in, so I figure, what the heck, I have an even bigger battery now. And I also went back to one starting battery and one deep cycle because before the lightning strike, the last set I had like that lasted over 5 years and still turned the motor better than the 2 year old WM batteries. This was deja vu as I have had bad experiences with WM batteries many years ago which was what caused me to stop buying them in the first place.

It was so nice to put the 6 amp charger on them and have them draw less than an amp after full charge...like a good battery should.

[dlandersson]

FYI, I have a pair of Walmart non-deep cycle batteries. Bought them in 2011. Use batteryTender in the winter.

When they go, I'll just get another set at Walmart. Life is too short.

[Boblee]

I have been doing a fair bit of research and Ctek seem to be excellent though a little pricey chargers that will handle both AC and solar panel input. It is not just the cost of ruining batteries but the hassle when you are out on the water and your fridge won't run or I have to use the auxiliary power pack to start the outboard.

Would have agreed with you until my C-tek died and I got a Projecta which gives you more control and choices with similar or as good control.
Both our boat batteries are now calcium and really only have one AGM left, the c-tek apparently works it out but with the projecta you need to select the type although I rang a technician and he said because our AGM is European the charger will probably detect it needs 14.8v to charge rather than the normal 14.4v.
The problem is there are so many different chemistries and charging alogorithms especially with batteries from all over the world and rebranded types you have to have an intelligent charger today.
Most good batteries today are ten year build but it means nothing if they are not charged correctly.
I picked up a battery from my grandson the other day (calcium) which he said was no good, so put it on the charger and it failed 3 times and was getting hot and venting, left it overnight and it came up ok, checked it again this morning and spot on, obviously the equalisation and recondition modes did the job but it will be damaged.

[Seapup]

got a Projecta which gives you more control and choices with similar or as good control.

I had not seen that projecta intelli-charger before. I don't think we have them in the US. Pricey, but it looks like a very nice unit.

[Boblee]

They are cheaper than the C-tek here but are made here, unlike the c-tek you actually set the battery type and you can also set the charge rate from 2-25 amps which is handy if you are running it in a remote position through an inverter to beat voltage drop which we do when travelling so that we arrive with fully charged batteries.
The projecta also gives volt and amps readouts, on our last trip we had to guess or try and put an ammeter in line to try and stop the inverter dropping out but with this one would only have to adjust the charge rate until it dropped as charge progressed or voltage rises.
Of course we could have used a DC to DC charger but we already had the gear and besides they also can have the same problem if the supply is too remote or charge rate is not adjustable.
The Grandson rang up last night and he is now buying a smaller Genius charger (3.5 amp) which are getting rave reviews here, so he will be able to use the AGM or the calcium batteries here now.

[DaveB]

I have twin group 29 deep cycles walmart for house and one 24 deep cycle walmart for starter. they are separated by a diode and charged independent thru 10 amp auto charger 110 and motor .
On them for 3 years and work great, just ck fluid every 6 mo. or more often if you run them down to 60% discharge. also have 90 watt solar panels for long trips.
They also have charge moniters and prevent discharge.
$85 each 29 and $80 for 24.
Trojan 6volt golf batteries for twin house is another good way to go for same price.
I run refig. and other elects. to require the twin house batteries.
This is what you need to combine batteries.
http://www.yandina.com/c100InfoR3.htm
I have my boat on a trailer with a ac cord connected to my auto 10 amp charger and auto charge house and starter batteries separate.
Those who don't have ac charger can hook up a 10- 40 watt solar panel to keep batteries up.
Dave

They are cheaper than the C-tek here but are made here, unlike the c-tek you actually set the battery type and you can also set the charge rate from 2-25 amps which is handy if you are running it in a remote position through an inverter to beat voltage drop which we do when travelling so that we arrive with fully charged batteries.
The projecta also gives volt and amps readouts, on our last trip we had to guess or try and put an ammeter in line to try and stop the inverter dropping out but with this one would only have to adjust the charge rate until it dropped as charge progressed or voltage rises.
Of course we could have used a DC to DC charger but we already had the gear and besides they also can have the same problem if the supply is too remote or charge rate is not adjustable.
The Grandson rang up last night and he is now buying a smaller Genius charger (3.5 amp) which are getting rave reviews here, so he will be able to use the AGM or the calcium batteries here now.

[raycarlson]

Resist the urge to go Hi Tech..... the cost of the new battery's is just a start. Then you have to double the cost because you have to buy a new Hi-Tech charger along with assorted gauges etc. Unless your in a submarine or sealed cabin sick with decades old flooded cell batteries, they can't be beat for dependability,simplicity and if maintained with an hour or two a year of preventive maintenance they will last as long as any of the newer technologies.

[RobertB]

I agree that if you do not have a good marine battery charger, then use lead acid batteries. I do caution against using starting batteries since a deep discharge can often do irreparable damage - use deep cycle. And be very careful with the battery charging.
I invested in a ProMariner battery charger and now run three batteries. One is the one of the original bargain batteries from the dealer, the second is a WM deep cycle gell, and the third is my reserve starting battery, a Sears DieHard from my departed minivan. The battery charger charges and maintains the batteries independently - no worries, no issues. I went thru two batteries the first year using a reasonable car battery charger (one of them a lead acid one) but since upgrading, never had an issue since.

[bartmac]

What most people don't realise that charging a battery to about 85-90% is easy and fast....its the last 10-15% that takes the longest...as the battery voltage rises the amperage drops away rapidly....if it didn't the voltage would continue to rise damaging the battery especially AGM or gell

[Russ]

FYI, I have a pair of Walmart non-deep cycle batteries. Bought them in 2011. Use batteryTender in the winter.

When they go, I'll just get another set at Walmart. Life is too short.

Agreed.
That's what I'm doing come spring.

Cheap, good quality and .... cheap.

[DaveB]

Robert, It is best to use all new deep cycle batteries. I use twin 29 for house and group 24 for starter. both are separate charged from AC 10 amp builtin charger and charge from outboard. They always remain separate but can combine with the on off 1-2 both selector switch.
Voltage from deep cycle and reg. non deep cycle have different voltage when charge or high end. (why to keep all deep cycle to have same voltage )
Disregard those who say you need a non deep cycle battery for starting motor.
I use a refig. and many people don't relize why we need twin house batteries.
Over 3 years still running two group 29 house and one group 24 batteries, all marine deep cycle Walmart.
When they go bad I will go back to twin 6volt Trojan golf cart batteries for house, stay with 12 volt 24 group Walmart starting battery.
Dave

I agree that if you do not have a good marine battery charger, then use lead acid batteries. I do caution against using starting batteries since a deep discharge can often do irreparable damage - use deep cycle. And be very careful with the battery charging.
I invested in a ProMariner battery charger and now run three batteries. One is the one of the original bargain batteries from the dealer, the second is a WM deep cycle gell, and the third is my reserve starting battery, a Sears DieHard from my departed minivan. The battery charger charges and maintains the batteries independently - no worries, no issues. I went thru two batteries the first year using a reasonable car battery charger (one of them a lead acid one) but since upgrading, never had an issue since.

[raycarlson]

with charger like Promariner with 2-3 independent charging leads which isolates each battery to it's self there is no need to use the same brand, age of battery, that's mainly a marketing strategy to sell more battery's, best investment is small voltmeter to check charged battery after resting 24hrs for true state of charge.