My 208 adventure has 2 size 24 starting batteries which both have a 1000 mca. Do I have to replace both them at the same time? Can I replace one with a starting and the other with a duel purpose?
Replacing batteries
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Mustang65fbk
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Do you need to replace the batteries currently or are you talking about hypothetically in the future? If one was bad and not the other, I don't see why you couldn't change out just the one and leave the other until it needed to be swapped out. If the boat runs and works right now, I don't see why you wouldn't be able to replace them with the current setup you have in there. Are there date codes punched out on the stickers of the batteries? I just bought my boat back in October and if/when I need to swap them out, I'll likely get some Interstate brand batteries from Costco when I do.
I dont know where to find a punch date on the batteries. The motor starts now and all I have is a fishfinder/GPS and radio and bilge if I'm drifting while fishing. I honestly don't know anything about batteries and don't want be stranded do to old batteries
Hookup1
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Install a pair of Duracell AGM Marine Group 34M's from Sam's Club. Great deal and great batteries.
Fishtales
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Usually the batteries are wired in parallel in one bank. You should be able to change just one of them. I have 2 banks of 2 and usually replace two at a time, but you don't have to. The Duracell are good batteries - 2nd them.
If I install 34s I'll have to replace my battery pans right? Because they are bigger batteries? Do I have to get 2 starters or can I get a starter and a dual purpose?
Hookup1
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I think your pans are the right size.
Group 34M Length:10.75 in. Width:6.875 in. Height:8.375 in vs.
Group 24 - Length:10.75 in. Width:6.75 in Height:9 in
These batteries are dual purpose starting and deep cycle. I use two 34M's for the engines, a 27M for the house and a 34M for bow thruster and windlass.
I'm using all Duracell Marine AGM's purchased at Sam's Club. These prices have been updated.
Group 34M 43.10 lbs. 955 MCA 55 AH. $124.88
Group 24M 52.40 lbs. 800 MCA 78 AH. Did not see availability at my store.
Group 27M 61.55 lbs. 900 MCA 92 AH. $168.44
Group 31M 67.35 lbs. 1,000 MCA 105 AH. $189.52
Group 34M Length:10.75 in. Width:6.875 in. Height:8.375 in vs.
Group 24 - Length:10.75 in. Width:6.75 in Height:9 in
These batteries are dual purpose starting and deep cycle. I use two 34M's for the engines, a 27M for the house and a 34M for bow thruster and windlass.
I'm using all Duracell Marine AGM's purchased at Sam's Club. These prices have been updated.
Group 34M 43.10 lbs. 955 MCA 55 AH. $124.88
Group 24M 52.40 lbs. 800 MCA 78 AH. Did not see availability at my store.
Group 27M 61.55 lbs. 900 MCA 92 AH. $168.44
Group 31M 67.35 lbs. 1,000 MCA 105 AH. $189.52
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Starting batteries are what the boat was originally equipped with and what the Yamaha service manual recommends.. Unless you have a lot of electrical load, they should work fine. Mine last me 7 seasons and I leave them in the boat during winter storage ( disconnected of course and fully charged before disconnecting). I do not have a lot of accessory loads.
It is best to replace both at the same time and also use the same battery type.
That boat is wired with one battery switch and that means that both the starting load and the running (house) load will be drawn from the battery selected, one, two or Both.
If you install a deep cycle battery, when selected the motor will also use it as its starting battery.
I initially start and run on one battery which I change between the two batteries. On the return trip, depending on how long the run is, I will select BOTH to top off both batteries
ot
It is best to replace both at the same time and also use the same battery type.
That boat is wired with one battery switch and that means that both the starting load and the running (house) load will be drawn from the battery selected, one, two or Both.
If you install a deep cycle battery, when selected the motor will also use it as its starting battery.
I initially start and run on one battery which I change between the two batteries. On the return trip, depending on how long the run is, I will select BOTH to top off both batteries
ot
Mustang65fbk
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Most batteries will have a sticker on the top of them with months and years, of which typically when you buy them from a store they'll use a hole punch and knock out the corresponding month and year they were purchased in. If everything works now, I say either test them yourself if you have a battery tester, or pull them and take them to your local auto parts store and have them tested there. If you don't want to do that and just want the extra peace of mind then sure, buy two new ones and call it a day.
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Always replace both - paralleling batteries with a bad battery, will cause problems.a bad battery will bring down a good battery
Chessie246G
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Agreed if the batteries are wired parallel the and one battery is bad it will pull down the good battery. Parallel wiring the batteries will constantly try to equal themselves out. If parallel replace both of them. If not then no reason to replace both. Pull them and have a good quality load test done, not the little handheld tester at the auto parts store.
SkunkBoat
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you don't need 34s. They probably won't fit and they cost more and you don't need that much battery.
A pair of 24M or 24DP will be fine. Don't overthink it
You have a standard single motor/2 battery setup with a 1/Both/2/Off switch.
You don't have parallel batteries. ( The Both position makes them parallel)
An improvement would be reconfiguring from the standard grady single motor/ 2 battery setup.
They run the House off the start cable to the motor. Whichever battery you have the switch set to will start, run House and charge.
The other one does nothing and does not charge.
You have to rotate battery switch position in some regular pattern like 1 heading out ,2 coming in. Or every trip use a different one.
Thats just stupid but it works for a lot of people. You run the risk of using only one of the batteries all the time and never charging the other.
Some people put the switch on BOTH to charge both and that is really stupid.
A better setup is separating the function of the batteries. Make one a starter baterry and the other a House battery. Have both of them charge all the time.
You can look on Blue Seas website for single motor/ 2 battery setups.
A pair of 24M or 24DP will be fine. Don't overthink it
You have a standard single motor/2 battery setup with a 1/Both/2/Off switch.
You don't have parallel batteries. ( The Both position makes them parallel)
An improvement would be reconfiguring from the standard grady single motor/ 2 battery setup.
They run the House off the start cable to the motor. Whichever battery you have the switch set to will start, run House and charge.
The other one does nothing and does not charge.
You have to rotate battery switch position in some regular pattern like 1 heading out ,2 coming in. Or every trip use a different one.
Thats just stupid but it works for a lot of people. You run the risk of using only one of the batteries all the time and never charging the other.
Some people put the switch on BOTH to charge both and that is really stupid.
A better setup is separating the function of the batteries. Make one a starter baterry and the other a House battery. Have both of them charge all the time.
You can look on Blue Seas website for single motor/ 2 battery setups.
Okay thanks guys. I'm just worried running one battery to destination and running my battery with the motor off while drifting will drain it and won't be able to get home. Should I drive to my spot then switch to my second battery to drift then switch back to both on my drive home to charge them?
Chessie246G
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dual batteries,, one dedicated house for all accessories, one dedicated engine. blue seas ACR and battery switch. maybe a $150 investment. the acr only closes when it senses charging voltage, to charge you house battery when the engine is running or hooked up to a charger. also gives you the option to switch to both batteries incase of a failure. easiest and simplest solution.
I'm a complete newbie here I have the switch for 1, 2,or all. Can we all explain? I understand switch 1 goes to one battery switch 2 goes to second battery and all switch is both. When should I alternate? I don't know what your saying saying about the arc is all about. Maybe I am over thinking this all.
SkunkBoat
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there are a lot of threads on this site about batteries. Try searching "battery" and "Battery switch" for more info from old posts.
Look for single motor and dual battery configurations. Ignore all talk of parallel battery banks and 4 batteries.
You have this. The motor Start and House power are both on the COM (common) post.
Whichever battery you choose starts the motor and runs all 12v lights and electronics and pumps and charges from the motor.
The other battery does nothing and does not charge.
YOU have to manage your battery charge by alternating between 1 to 2. Don't run on BOTH.
Running on both would SEEM like an answer but it completely defeats the purpose of having a "backup" battery.
When you are on BOTH, the batteries are parallel. You effectively have ONE bigger battery. Thats good for running electronics or starting a motor but you have no "spare"
If you have a bad battery and switch to BOTH you will have TWO bad batteries shortly.
BOTH is for when you tried 1 and could not start and then tried 2 and could not start and then said oh shit cross your fingers maybe both of these bad batteries together will get me started.
This below is better. B1(Start) and B2(House) are separated. There is a Start battery on the 1 pins and a House battery on the 2 pins
The start battery does not run anything. it just starts the motor and charges up for the next time you need to start.The running motor charges the start battery.
The ACR routes the charge to the House battery when needed.
The house battery runs your 12v stuff and does not start the motor. Starting your motor won't dip the House 12v and cause things to blink off.
In this configuration you are USING both batteries but for different purposes. You can even use a deep cycle battery for the house
The diagram shows a Negative Bus. You could substitute a that with the existing negative battery jumper (from -B1 to -B2) that is on your boat now and make other negative connections to either negative battery post.
This diagram shows optional "Start Interrupt" or SI. Its not necessary, so all that key switch connection can be ignored.
https://www.bluesea.com/products/7649/Mini_Add-A-Battery_Kit_-_65A
They have a kit that includes an AC charger https://www.bluesea.com/products/7655/Mini_Add-A-Battery_Plus_Kit_-_65A_[North_America]
There are other ways to do this but I won't go there now.
Look for single motor and dual battery configurations. Ignore all talk of parallel battery banks and 4 batteries.
You have this. The motor Start and House power are both on the COM (common) post.
Whichever battery you choose starts the motor and runs all 12v lights and electronics and pumps and charges from the motor.
The other battery does nothing and does not charge.
YOU have to manage your battery charge by alternating between 1 to 2. Don't run on BOTH.
Running on both would SEEM like an answer but it completely defeats the purpose of having a "backup" battery.
When you are on BOTH, the batteries are parallel. You effectively have ONE bigger battery. Thats good for running electronics or starting a motor but you have no "spare"
If you have a bad battery and switch to BOTH you will have TWO bad batteries shortly.
BOTH is for when you tried 1 and could not start and then tried 2 and could not start and then said oh shit cross your fingers maybe both of these bad batteries together will get me started.
This below is better. B1(Start) and B2(House) are separated. There is a Start battery on the 1 pins and a House battery on the 2 pins
The start battery does not run anything. it just starts the motor and charges up for the next time you need to start.The running motor charges the start battery.
The ACR routes the charge to the House battery when needed.
The house battery runs your 12v stuff and does not start the motor. Starting your motor won't dip the House 12v and cause things to blink off.
In this configuration you are USING both batteries but for different purposes. You can even use a deep cycle battery for the house
The diagram shows a Negative Bus. You could substitute a that with the existing negative battery jumper (from -B1 to -B2) that is on your boat now and make other negative connections to either negative battery post.
This diagram shows optional "Start Interrupt" or SI. Its not necessary, so all that key switch connection can be ignored.
https://www.bluesea.com/products/7649/Mini_Add-A-Battery_Kit_-_65A
They have a kit that includes an AC charger https://www.bluesea.com/products/7655/Mini_Add-A-Battery_Plus_Kit_-_65A_[North_America]
There are other ways to do this but I won't go there now.
The factory orig equip is a simple setup and appropriate for the boat. You don't need to go nuts with upgrades. I probably have said this 100 times but run on one battery. Alternate which battery that is but don't go nuts trying to use both equally. One approach is to use battery 1 on odd dates and battery 2 on even dates. Sometime if my return trip will be longish ( 20 minutes or more) and at a cruising speed, I will make the return trip on BOTH to give a little charge to both batteries
Note that with the config you have, the battery switch selects which battery powers the motor and the accessories. In other words, the starting battery and the house battery are the same battery. Let's say you are running on 1, motor to a place, anchor, crank up the 'megawatt' stereo or whatever and fall asleep. You wake up and try to start the motor discovering you ran down your battery. No problem, you switch to the other battery, start the motor and head home.
Some day as your batteries get older and need replacement, you might experience a situation where your battery doesn't have enough juice to start your motor, so you select the other battery only to have the same issue.In that case select BOTH and often the two together will have enough capacity to get you home.
You may be aware of this info but to be sure, never turn the battery switch past OFF while the motor is running. On some engines, that can damage the rectifier.
So 1-BOTH-2 is OK as is 2-BOTH-1 or 1-BOTH or 2-BOTH but never 1-OFF-2
Note that with the config you have, the battery switch selects which battery powers the motor and the accessories. In other words, the starting battery and the house battery are the same battery. Let's say you are running on 1, motor to a place, anchor, crank up the 'megawatt' stereo or whatever and fall asleep. You wake up and try to start the motor discovering you ran down your battery. No problem, you switch to the other battery, start the motor and head home.
Some day as your batteries get older and need replacement, you might experience a situation where your battery doesn't have enough juice to start your motor, so you select the other battery only to have the same issue.In that case select BOTH and often the two together will have enough capacity to get you home.
You may be aware of this info but to be sure, never turn the battery switch past OFF while the motor is running. On some engines, that can damage the rectifier.
So 1-BOTH-2 is OK as is 2-BOTH-1 or 1-BOTH or 2-BOTH but never 1-OFF-2
SkunkBoat
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here is a well written descritpiion of 1/2/both switching.
https://marinehowto.com/1-2-both-battery-switch-considerations/
https://marinehowto.com/1-2-both-battery-switch-considerations/
Well if the OP was confused before, his head is swimming now. Way too much info for a newbie to marine battery application
Even I had to stop every now and then and give my brains a second to catch its breath.
I pretty much agree on everything and even learned something about cold cranking amps.
However, since it is not in my nature to accept everything, I need to point out that I disagree with the author's statement that it is perfectly OK to use a deep cycle battery as a starting.
Just this morning while researching info on Optimax troubleshooting , I read again and it was explicit that Only starting type batteries should be used for starting. That statement is also noted in the Optimax owner's manual.
I can attest to the fact that Optimaxs ( at least the ones I have on one of my fleet boat) are very picky about starting voltage and if the voltage is a tad low, the motors will crank forever but not fire up. There may be reasons other than or in addition to the motors being Optimax but some times, a cold motor will not fire unless BOTH is selected. I have tried to identify why that is but at this point in time, if a cold motor doesn't fire up, I just switch to BOTH and vroooom, the motor fires.
Thanks for the link to that article.
Even I had to stop every now and then and give my brains a second to catch its breath.
I pretty much agree on everything and even learned something about cold cranking amps.
However, since it is not in my nature to accept everything, I need to point out that I disagree with the author's statement that it is perfectly OK to use a deep cycle battery as a starting.
Just this morning while researching info on Optimax troubleshooting , I read again and it was explicit that Only starting type batteries should be used for starting. That statement is also noted in the Optimax owner's manual.
I can attest to the fact that Optimaxs ( at least the ones I have on one of my fleet boat) are very picky about starting voltage and if the voltage is a tad low, the motors will crank forever but not fire up. There may be reasons other than or in addition to the motors being Optimax but some times, a cold motor will not fire unless BOTH is selected. I have tried to identify why that is but at this point in time, if a cold motor doesn't fire up, I just switch to BOTH and vroooom, the motor fires.
Thanks for the link to that article.