Battery Question for certified Marine Mechanic

[ol guy]

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]

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]

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-]

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-]

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-]

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']

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]

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

[ahsumtoy]

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]

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?
Brown has decided not to answer your question, as he thinks it's silly ....and non relevent....