Battery Question for certified Marine Mechanic [Archive]

Classic Daycruiser

08-13-2007, 08:13 PM

The only difference between the blue (marine) and yellow (deep cycle) Optimas are the terminals.
I think the question should be deep cycle vs starting battery.
I heard from an un relible source, that marine batteries has a fuse inside that breaks if you sumerge them. Reduced risk of exploisions...etc. But I want to here it from a certified mechanic....Whats the scoop:idea:
Maybe we should call myth busters??? again

CoolCruzinCobra

08-13-2007, 08:15 PM

This is what I run.
Number one auto battery for starting
Number two is a marine battery .
I use number two when blasting the stereo .
The marine can take a draw longer.
The auto can supply more cracking amps to start.

Baja Big Dog

08-13-2007, 08:17 PM

Being an electrical engineer, I could answer you question, but IM not a certified marine mechanic!!!

phebus

08-13-2007, 08:20 PM

The main difference between a Marine battery, and others is that anything marked Marine is usually twice the cost. :D

Tom Brown

08-13-2007, 08:21 PM

I heard from an un relible source, that marine batteries has a fuse inside that breaks if you sumerge them. Reduced risk of exploisions...etc. But I want to here it from a certified mechanic....Whats the scoop:idea:
A battery that stops working when you get water in the bilge might not be the best idea for a marine battery. Also, batteries don't explode when they get wet. In fact, they will happily work submerged.
I'm with HH. The only difference is the terminals. Marine batteries tend to use 3/8" thread side terminals while car batteries use top posts.
There's no need to call Myth Busters.... or Mensa.
What makes you think marine mechanic certification involves a deep understanding of the construction of batteries?

Tom Brown

08-13-2007, 08:22 PM

i'm calln BULLSHIT ON THIS,whats the other 100$ for?
Boat tax.

Havasu Hangin'

08-13-2007, 08:22 PM

I heard from an un relible source, that marine batteries has a fuse inside that breaks if you sumerge them. Reduced risk of exploisions...etc. But I want to here it from a certified mechanic....Whats the scoop:idea:
Maybe we should call myth busters???
Not sure about that...lol. I believe batteries need oxygen, hydrogen, and a spark to ignite, so they will not explode when submerged...they just leak acid...which a fuse won't help.
I think there was a Merc bulletin awhile ago about deep cycle batteries screwing with the computer on the newer engines? Anyway, most agreed that as long as the voltage doesn't drop during long cranking, a deep cycle (marine) will work just as good as a starting battery with those computers.
Just make sure the CCA meets the requirements for your motor.

Jordy

08-13-2007, 08:27 PM

I'm with HH. The only difference is the terminals. Marine batteries tend to use 3/8" thread side terminals while car batteries use top posts.
Most marine batteries use threaded terminals, at least down this way and anymore most car batteries use the side terminals. I know you crazy Canadians like to do things differently though. :D
There's no need to call Myth Busters.... or Mensa.
Not with all the know it alls who hang out in this place. :D
What makes you think marine mechanic certification involves a deep understanding of the construction of batteries?
And even more importantly, what makes you think that you're going to find a certified marine mechanic who will post on here, in The Sandbar, and give you an answer that the rest of the know it alls will even come close to agreeing with??? Are you new??? :idea:

ol guy

08-13-2007, 10:05 PM

Marine is a sealed battery to detour emision of acid into waterways incase of capsize and to contain acid fume emision from an enclosed engine compartment usually caused by over charge or poor connection.

ol guy

08-13-2007, 10:37 PM

Hey RIODOG. The electrolosis is caused by the fact thet electricity will find the easiest ground and in water it will take the " FORGIVING METAL ". This is why ocean boats will always use a zinc or in some cases lead plugs situated somewhere under water to absorb the electrolosis created by a boat seating in a ungrounded atmosphere. As a daily but that drowns and sits under water for any length of time. At which point the alumium becomes the forgiving metal. And You are very right I have never heard of an intearnaly fused battery.

brianthomas

08-14-2007, 03:53 AM

Not all marine batteries are sealed.
Marine batterys, deep cycle or starting have thicker plates and more reserve space under the plates for sediment, lead or calcium. Only use a starting battery for starting the engine, it is no more dangerous to use a marine battery or auto battery as long as the terminals are clean and connected well. Only use a deep cycle battery for things like stereos. NEVER set the battery switch on BOTH if you are mixing deep cycle and starting batterys unless you absolutely need to to start the boat. Switch the selector back to one or two depending on which battery you want to charge. You can run on BOTH setting if you have installed an isolator but most smaller boats do not have them. If you run on BOTH without an isolator you will likely forget to change it back to one or two when you shut the engine off and the lower voltage battery will be charged by the other battery, not a good way to go.
When changing the switch while the engine is running be very careful to never turn it through off as it will instantly fry your alternator. Only turn past both.

HOOTER SLED-

08-14-2007, 03:55 AM

deep cycle........................able to have power discharged and recharged multiple times more than just a standard battery. Thus the reason they are used for these types of applications. They have more reserve time. Standard/starting batteries will have more cranking amps. Maybe the original question being asked was this....................deep cycle vs. standard batteries.............the differences. I ain't no expert, but this was my stab at it. :) :)

HOOTER SLED-

08-14-2007, 03:56 AM

Marine batterys, deep cycle or starting have thicker plates and more reserve space under the plates for sediment, lead or calcium. Only use a starting battery for starting the engine, it is no more dangerous to use a marine battery or auto battery as long as the terminals are clean and connected well. Only use a deep cycle battery for things like stereos. NEVER set the battery switch on BOTH if you are mixing deep cycle and starting batterys unless you absolutely need to to start the boat. Switch the selector back to one or two depending on which battery you want to charge. You can run on BOTH setting if you have installed an isolator but most smaller boats do not have them. If you run on BOTH without an isolator you will likely forget to change it back to one or two when you shut the engine off and the lower voltage battery will be charged by the other battery, not a good way to go.
When changing the switch while the engine is running be very careful to never turn it through off as it will instantly fry your alternator. Only turn past both.
:D :D :D :)

HOOTER SLED-

08-14-2007, 03:59 AM

Another point..........................if you are bangin your stereo battery all day long........then start it up.........don't switch the battery switch to "both" either, as the weaker battery will draw from the stronger................am I correct?

Havasu Hangin'

08-14-2007, 04:12 AM

You can run on BOTH setting if you have installed an isolator but most smaller boats do not have them.
Which isolator works if they are on "both"?
Another point..........................if you are bangin your stereo battery all day long........then start it up.........don't switch the battery switch to "both" either, as the weaker battery will draw from the stronger................am I correct?
They will try to equalize each other. You will have the same amount of charge stored, it will just be distributed over two batteries instead of one.

Tom Brown

08-14-2007, 04:15 AM

Which isolator works if they are on "both"?
It's the Andrew Speaker isolation mode.

ahsumtoy

08-14-2007, 04:22 AM

What about using battery tenders on deep cycle batteries? I have two deep cycles that I keep two seperate tenders on and the batteries seem to never stay charged. If a put a regular charger on them, or just run the boat, they charge up. Any idea what I'm doing wrong?

Jbb

08-14-2007, 04:27 AM

Tom Brown

08-14-2007, 04:35 AM

Brown has decided not to answer your question, as he thinks it's silly ....and non relevent....
That's a quality effort, right there. lmao! :D :D :D :D
Since I know when my ass is kicked....
Ahsumtoy, make sure the tenders are making good connections directly to the batteries and not switched power. Also, check the connections for corrosion as this will cause resistance.
From there, check your battery voltage and make sure it goes up a tiny bit when the tenders are plugged-in. If the voltage doesn't go up a tiny bit with the tenders connected, re-check your connections and make sure you're connecting directly to each battery. If everything is OK, you might look for a fuse in the battery tender. The easiest thing would be to check the voltage across the output of the tender when it's disconnected from it's battery.

Dave C

08-14-2007, 08:35 AM

Marine Battery... LOL... thats almost as funny as a "marine" car-boat motor. LMAO!!:devil:
the question should be. what battery is best for my stereo ;)

brianthomas

08-14-2007, 12:12 PM

This point is impossible to prove one way or another, but let me be the first to state I doubt Optima tools up to build 40 different skus.
I have not owned Optimas but I seem to remember they are absorbed glass mat batterys, completely different animal.

brianthomas

08-14-2007, 12:23 PM

Which isolator works if they are on "both"?
They will try to equalize each other. You will have the same amount of charge stored, it will just be distributed over two batteries instead of one.
Isolators keep a fully charged battery from discharging into a discharged battery when they re connected in parallel or the switch is set to "both."
I'm never positive if I am doing it right on my boat but I have two group 31s in parallel for each the starboard and port motors. These systems are completely separate just in case one engine or battery bank has a malfunction. I do have a switch on the dash that activates a solonoid to parallel the starboard and port sides if one side is too low to start the engine. You start the engine that will start and then hold the button in and start the engine that has low batterys. Works great.
I also have a group 24 cranking battery that is hooked to nothing but the generator. That way the gen. will always start and I can flip on the onboard charger that is connected to the engine batterys and provides 40 amps.
A sixth battery is an 8D like you would see in a medium duty truck to start a diesel. This is a 165 lb. battery and it is connected to a 3,000 watt inverter so the whole boat has AC 115 volt power. The inverter is also a charger just for the 8D at a rate of 125 amps. There is a intuitive control panel for this inverter and battery to monitor all of the functions and capacities. This 8D battery is actually an absorbed glass mat or AGM but the dimensions and weight are the same with a lead/acid battery. Oh, the inverter will run things like the microwave, tvs and fans but not the air conditioner.
I'm not an expert, this is just what I have had the best luck with and I have owned many boats. Just happens the boat I have now is pretty big.

Havasu Hangin'

08-14-2007, 12:38 PM

Isolators keep a fully charged battery from discharging into a discharged battery when they re connected in parallel or the switch is set to "both."
I'm never positive if I am doing it right on my boat but I have two group 31s in parallel for each the starboard and port motors. These systems are completely separate just in case one engine or battery bank has a malfunction. I do have a switch on the dash that activates a solonoid to parallel the starboard and port sides if one side is too low to start the engine. You start the engine that will start and then hold the button in and start the engine that has low batterys. Works great.
There are really two types of isolators- diode and solenoid.
Diode Isolators use diodes on the charging system to isolate the alternator charge without tieing the batteries together through the charging wire. When you put any battery switch on "both"...it negates the diodes.
Solenoid isolators actually phisically interupt the circuit. However, once again, if you switch the batteries to "both", it will negate the isolator...
...unless Tom Brown wired it.
I also have the parallel solenoid you are talking about. All that does is tie the batteries in parallel for a few seconds so you can start your engines. You could accomplish the same thing by running back and switching the Perko switch to "both".

Classic Daycruiser

08-14-2007, 12:52 PM

Being an electrical engineer, I could answer you question, but IM not a certified marine mechanic!!!
Thank you:D :D

Classic Daycruiser

08-14-2007, 01:01 PM

You can tell your source that he don't know sh*t. I put one on the botton about 10 years ago Sat afternoon and brought it back up Sunday morning and the bilge pumps were still working and the biggest damage came from the battery grounding itself to the metal of the engine. Everypiece of polished aluminum had to be repolished from the electrolosys. The bats were optina blue tops/1000cca. I still use one of them in the boat.
Rio
I did say "un" reliable. I still have not found a certified mechanic that can give me the correct answer.
Do you think this is a trade secert?

Classic Daycruiser

08-14-2007, 01:15 PM

When all else fails...bring backup:idea:
http://www.***boat.com/forums/attachment.php?attachmentid=37064&stc=1&d=1187126561

HOOTER SLED-

08-14-2007, 02:52 PM

They will try to equalize each other. You will have the same amount of charge stored, it will just be distributed over two batteries instead of one.
That's what I meant. :D

brianthomas

08-14-2007, 03:13 PM

That's what I meant. :D
Exactly. Many people will run on battery number one and once they anchor out will switch to battery number two for the stereo. Hours later they switch back to battery one to start the boat and leave. With an in line isolator they could then go to both without the fear of battery number one being drained by battery number two while running back to the marina. An isolator is just a one way valve so the alternator can quickly charge up the starting battery that will likely take only a very few minutes and then charge battery two with all of it's available amperage. This happens while not tearing down battery one. You can manage it just using the switch but it is all automtic this way, convenience is all it is.

brianthomas

08-14-2007, 03:17 PM

There are really two types of isolators- diode and solenoid.
Diode Isolators use diodes on the charging system to isolate the alternator charge without tieing the batteries together through the charging wire. When you put any battery switch on "both"...it negates the diodes.
Solenoid isolators actually phisically interupt the circuit. However, once again, if you switch the batteries to "both", it will negate the isolator...
...unless Tom Brown wired it.
I also have the parallel solenoid you are talking about. All that does is tie the batteries in parallel fo a few seconds so you can start your engines. You could accomplish the same thing by running back and switching the Perko switch to "both".
With the parallel solenoid it completely eliminates the need for a manual battery switch that would tie the two engines together. Much easier also. My port battery bank runs the refrigerators and if I have been anchored out I will start the starboard engine first, turn the ignition on on the port and check the voltage, if it is low at all I will push the parallel switch just to not have low voltage to the starter brushes. Marine starters are expensive and love all the voltage they can get.

Kyote

08-14-2007, 03:25 PM

I heard from an un relible source, that marine batteries has a fuse inside that breaks if you sumerge them. Reduced risk of exploisions...etc. But I want to here it from a certified mechanic....Whats the scoop:idea:
Maybe we should call myth busters??? again
Actually the fuse is there to protect the electrical circuit in cases where the boat is SPUN into the reeds. The centrifical force breaks the circuit. This is a self reseting fuse that will activate after the driver has cleaned his shorts. The reactivation of this fuse allows the boat operator to post a report of his actions on the ***boat Forums so that he can inform any other boaters in the area that they were resposible for his actions.
BTW- I am not a certified marine mechanic. I am working on my ***boat Forum Certification for the BS section.

Havasu Hangin'

08-14-2007, 03:25 PM

With the parallel solenoid it completely eliminates the need for a manual battery switch that would tie the two engines together. Much easier also. My port battery bank runs the refrigerators and if I have been anchored out I will start the starboard engine first, turn the ignition on on the port and check the voltage, if it is low at all I will push the parallel switch just to not have low voltage to the starter brushes. Marine starters are expensive and love all the voltage they can get.
What happens when you kill the port battery, your fridge quits, and your beer gets warm?
You gonna hold that button down for a few hours while your beer gets cold again?

brianthomas

08-14-2007, 04:08 PM

What happens when you kill the port battery, your fridge quits, and your beer gets warm?
You gonna hold that button down for a few hours while your beer gets cold again?
Oh god no, holding the button is why I brought my wife!:D
I only recently installed the inverter system and run both refrigerators on that system. Used to have the port pair of group 31s pretty low after 24 hours on the hook. Now we run the gen. every morning when we are anchored out to heat water for showers and charge all the batterys. The inverter will power the water heater but would not last very long.
Really has been interesting and kind of fun learning how to manage the power supplies and needs of this boat. A good friend retired from John Deere and then went to Marine Mechanics Institute in Florida for 18 months. He started a business working on marine and RV air conditioning systems and refrigeration. The inverter business is not enough to keep him busy. I assisted when he installed mine and learned a bunch.

rrrr

08-14-2007, 06:01 PM

A good friend retired from John Deere and then went to Marine Mechanics Institute in Florida for 18 months. He started a business working on marine and RV air conditioning systems and refrigeration. The inverter business is not enough to keep him busy. I assisted when he installed mine and learned a bunch.
Yeah, but is he certified?
:D

brianthomas

08-14-2007, 06:13 PM

Yeah, but is he certified?
:D
Hellifiknow? He has a diploma and is lots smarter about this stuff than anyone I know.

2manymustangs

08-15-2007, 06:27 AM

I did say "un" reliable. I still have not found a certified mechanic that can give me the correct answer.
Do you think this is a trade secert?
I have a call into a tech person at Exide down in Atlanta, my sister worked there for years and seems to think that all the plates are pretty much the same. I will see if there is a difference in plates, case OR electrolite.
My father in law runs FIFTEEN car batteries in his 50' Carver. He get's them from Costco and has good luck with them. Running the inverters, bow thruster, Raytheon gear, marine radios, anchor and starting the twin 650 cubic inch cummins turbo diesels. I have run large car batteries in my tractors and back hoe's for a long while with no problems.
I'm VERY surprised that Tom Brown can't answer this question.:D