Adding another 2 house batteries....Need suggestions

[jwrape]

I've been told by the expert Onan guy on the SmokStak Forum that it only has a small internal charge circuit to keep the coil energized like a stator on a motorcycle engine but the starter battery is only charged by the on board charger that is seperate, that runs on 110v- option 1

J,

I hate to rain on your parade and I'll sign off after this as it seems your intent in doing it a certian way so by all means- do what makes sense to you.

The reply you received from Billy at SmokStak did not suggest condition 1.. it suggested condition 2. Here is his verbatim response:

" Your unit does not have an alternator. It has a small charging system built in. But most boats I worked on had an outside charger for the boat. Ran from shore power or generator power. "


His response appears accurate and is consistent with the Onan/Cummins manuals I have- although I don't have the manual for yours specifically. Unless you had another more in depth discussion, it seem your interpreting his response differently than I would and differrently than other on here have advised.

It's your boat and your call so all I can say is- best of luck with whatever you decide.

Iguess we are having a description mis-understanding... Maybe I am relaying the information incorrectly, but you understand by reading Bill;s comments what it has right?
I'm not good with terminalogy I am more mechanical than academic. Sorry for the confusion, I wasn't trying to mislead you.

So bascially the starter battery for the generator is charged by the charger supplied by the 110v shor or Generator power only. Right?

In otherwords it won't damage anything on the generator to add 2 more batteries right? I'm just trying to cover my bases.

[ready123]

I do have one but it's not always helpful.
But thanks for the offer.

I suggest you read it carefully... mine clearly says not to connect a charger to the genny battery.
It seems to me you do in fact have an internal charger for the genny battery only.
So I say again make the genny battery standalone... only connect it to the boat 12V ground bus.....

[jwrape]

I do have one but it's not always helpful.
But thanks for the offer.

I suggest you read it carefully... mine clearly says not to connect a charger to the genny battery.
It seems to me you do in fact have an internal charger for the genny battery only.
So I say again make the genny battery standalone... only connect it to the boat 12V ground bus.....

Ok, I understand now.... I didn't get it the first couple times, I'm sorry.
So to add more power to my house batteries i need to isolate the house and the gen from each other and add the additional 2 batteries to the house and that way the 110v charger is only on the house batteries... Is that correct?

[ready123]

I do have one but it's not always helpful.
But thanks for the offer.

I suggest you read it carefully... mine clearly says not to connect a charger to the genny battery.
It seems to me you do in fact have an internal charger for the genny battery only.
So I say again make the genny battery standalone... only connect it to the boat 12V ground bus.....

Ok, I understand now.... I didn't get it the first couple times, I'm sorry.
So to add more power to my house batteries i need to isolate the house and the gen from each other and add the additional 2 batteries to the house and that way the 110v charger is only on the house batteries... Is that correct?

Yes.. you got it that is how you should do it your way. Note I personally would make the step to ONE large house battery.

[jwrape]

I hope you guys aren't getting frustrated with me, I just didn't understand what you guys were saying initially and I am trying to figure out the best configuration for my use without destroying anything.
I think I understand it now.
Still a little foggy why my current 2 batteries in parallel is ok for the charging system of the Onan but adding more would fry it. Is that because of the Amperage being too much for the ol' Onan?

[jwrape]

Note I personally would make the step to ONE large house battery.

I like that idea but you say one large battery is better and then another guy said that a large battery is just the same cause it has a bunch of small cells in it as if I had 4 regular batteries, so I'm torn on whos opinion to go with.

I'm trying to get enough opinion to make a good decision.

[jwrape]

Ok, I understand now.... I didn't get it the first couple times, I'm sorry.
So to add more power to my house batteries i need to isolate the house and the gen from each other and add the additional 2 batteries to the house and that way the 110v charger is only on the house batteries... Is that correct?

Yes.. you got it that is how you should do it your way. Note I personally would make the step to ONE large house battery.

Ok so I am 99% certain this is what's right for my situation.
I will have to get a few more cables and build them up to make this work but seems to be an easy way to get the capacity I am looking for. Also i will only have to buy 3 new batteries instead of 4 if the Genni batt. won't be in the bank.

I think the only question here now is whether I should have 3 12v marine deep cycle house batteries or buy one of those large multi cell batteries?

What is the price differennce? The house batteries I have now are $90 each so I'm looking at $270 plus wiring to go that route.

I'm wondering besides just havign one battery to connect and maintain, is there other benefits to the once large high capacity battery?

[ready123]

I think the only question here now is whether I should have 3 12v marine deep cycle house batteries or buy one of those large multi cell batteries?
What is the price differennce? The house batteries I have now are $90 each so I'm looking at $270 plus wiring to go that route.
I'm wondering besides just havign one battery to connect and maintain, is there other benefits to the once large high capacity battery?

Look back in this thread for the reasons why one is better than several... both jav and myself went into some detail.
I would expect you could get a good large battery for what the wiring and those three would cost. I would look at Gel or AGM type.
Call one of these guys for Lifeline pricing:
http://www.lifelinebatteries.com/distributors.php?id=11
You still have not said what power you need?
4DL or 8DL may be what you need.

[jav]

I hope you guys aren't getting frustrated with me, I just didn't understand what you guys were saying initially and I am trying to figure out the best configuration for my use without destroying anything.
I think I understand it now.
Still a little foggy why my current 2 batteries in parallel is ok for the charging system of the Onan but adding more would fry it. Is that because of the Amperage being too much for the ol' Onan?

No problem don't sweat it.

Let me clear the fog for you on why your current 2 batteries in parallel for the Onan are OK and 2 more would not be.

The fact is, the first 2 were technically NOT correct... but- it's how someone did it and got away with it for some time. Just becuase it didn't fry the Onan charger immediatly, doesn't mean that was "correct" or that it hasn't hurt the units longevity. You mentioned it isn't working now... who knows, that may have contibuted to the failure.

It's like riding around in a pickup truck with 1 wheel that has only 3 lug nuts when it's supposed to have 6. You drive around for a year that way -and nothing happens... does it make it right? NO. Does it mean you can take 2 more off - NO.

Same thing- There's lots of good info on this thread. Read it all several times and don't stop there. There's tons of great info online- you just have to pay closer attention to the details. Instead of reading what you'd like believe- read it objectively and try to understand the "why" instead of just the "how".

Good luck.

[kevin babineau]

u could buy a really really long extension cord

[ready123]

Note I personally would make the step to ONE large house battery.

I like that idea but you say one large battery is better and then another guy said that a large battery is just the same cause it has a bunch of small cells in it as if I had 4 regular batteries, so I'm torn on whos opinion to go with.
I'm trying to get enough opinion to make a good decision.

I think you are drawing the wrong conclusion... what was said that one battery (which has multiple internal cells) can have the same end result if one cell of those multiples goes bad. It was not stated that this is as likely to happen as when four batteries with their own internal cells are used.... in fact I believe that one battery is less likely to fail in service as there are fewer things to go wrong.
You need to consider that one battery with factory connected cells is likely to be less failure prone vs 4 batteries (with their own multiple internal cells) that are connected together. Also it is likely that you could have more cells in the 4 battery bank vs the single battery bank.

You are making this too complex... and I could argue that you drive a Mercedes why don't you want to go that route inside your boat?

Heck, I have one large AGM house battery and I drive a Ford!

[kevin babineau]

my decisions are so much easier than u guys....i dont have any money...so i just get what is the cheapest...if i know a guy that has some used golf cart batteries i llseries those bad boys up or if there is a sale at walmart then thats what she gets...if i have to find old fat car jumpers cables at a tag sale and cut the wires and crimp the connectors on there...if i had to id run black garden hose on the roof for hot water...if it was cheaper id have monkeys turning the shaft and get rid on the engines...well that actually might be cheaper

[TC]

The weak link in the pack is the cell. One large battery has 6 cells, 3 smaller batteries has 18 cells. The fewer the cells, less chance of failure. Some one is going to say "then change that battery". Once the pack is a year old replacing one battery is not a good idea. The old ones drag down the new one.

[wowzer52]

I had an 8D in a boat one time as the house battery and when it went bad I had to change it by myself. That puppy was so heavy I left stains in my shorts . I will never use a BIG battery again. I would much rather use several smaller batteries because they are easier to handle. Smaller stains too.

[jwrape]

I could argue that you drive a Mercedes why don't you want to go that route inside your boat?

Heck, I have one large AGM house battery and I drive a Ford!

It is a Mercedes but it's the cheap one and I do all the maintenance myself. I know from appearences I may look like I have money, but honestly I am very tight and buy all my cars cash and have worked my way up from a 77' Primered Firebird to now driving a Mercedes. I buy low and sell high. In reality I would rather be driving my ol' 91 Mustang Convertible but I was stupid and sold it for the Benz.

I am very Blue collar with a semi-white collar job... I am a hands on type of person as we all are if we own a Trojan... My financial appearence just looks expensive but I am just really good at finding deals and fixing things. It's friendly folks like you guys on forums that make it possible for me to learn all this new information on how to make things perform better and ways to imporve on what the factory did half way.

I absolutely love forums, the best knowledge is sitting in someones head, not always in a book.... A lot of the times the modifications and upgrades are not written down in a manual so picking someones brain is the way to go.
That's how I figured out how to put the electronic ignition on my Onan of which there was not one made for it, that's how I figure out how to put a high torque starter on my Mustang, that's how I figure out how to put a GM high amp altenator on my Conquest Tsi - The folks on the forums know so much more than a certified technician does.... Gotta love the knowledge base on the forums...

Thanks guys!


I will got to batteries plus and check out their selection of Large batteries and see what I can get. I think, although it might break my back to get it in there I will give it a wurl....

Definately gonna isolate the generator battery now.