Adding a second Alt batt combo to 3.0L

[rlcate308]

How would I go about installing a second small sized Alt and batt combo to power my two stereo amps? My boat has a 2006 GM 3.0L Volvo Penta. I have a single pully balancer and single water pump pully. What I'm looking at is a small 2010-2011 Merc 115 outboard ALt... smaller size would be nice if any suggestions. Due to room constrainsts, I would like to run it same side (port) as the existing Alt. Can it be run off the water pump pully if a double groove pully is added and is there a bracket that will work for mounting? If no bracket, I can make one to fit. Is this outboard Alt usable in this fashion on an inboard and how would I wire it into the system?
side note: I have manual steering so there are no other pumps to work around..

 

[Don S]

Re: Adding a second Alt batt combo to 3.0L

You don't need a second alternator to run stereo amps, maybe a second battery with a battery switch so you use only 1 battery when the engine is off, but not a second alternator.

 

[Silvertip]

Re: Adding a second Alt batt combo to 3.0L

Or just replace the existing alternator with a larger capacity unit. Or as Don said. $30 for the switch and a few bucks more for some cables and you are in business.

 

[Bondo]

Re: Adding a second Alt batt combo to 3.0L

combo to power my two stereo amps?

Ayuh,... So What's the total amperage draw of 'em,..??

 

[86 century]

Re: Adding a second Alt batt combo to 3.0L

The others are correct about not needing a second battery pump. If you must there are pulleys out there find some for a 3.0l with power steering and make yourself a bracket.

Good Luck. If you do it let us see it.

 

[keninaz]

Re: Adding a second Alt batt combo to 3.0L

I would not bother with another alternator unless you know you are drawing more amperage from all needs than your current alternator will put out.
Why not just put in a second battery for use with your stereo that will power it when the motor is not running?
Many RVs are set up this way. You set it up as a house battery (boat battery in this case) that charges when the motor is running but you cannot run the starting battery down.

This post shows you how to do that~

http://forums.iboats.com/showthread.php?t=249593

 

[rlcate308]

Re: Adding a second Alt batt combo to 3.0L

I have the Amps on order and have not recieved them yet. The other components have been collected over the past few months Bass amp MR1000 4ch running two MR100 10" subs. (bridging 2ch per sub). Boss MR800 Amp for the front drivers (will pull 2ohms per side). two sets of MR652c drivers with removable tweets. Head unit is the MR1420w..... I like their products and have had good luck with them thus far.

I have a full Boss system in my truck and when the bass would hit, the head lights would dim. The solution was to add a capaciter to the bass side. I don't want to put a cap in a boat around water for obvious reasons, thus the question about a second alt and batt. Until I have the amps in hand, I will be unable to give a full set of draw numbers. I'm willing to try the second batt with a cut over switch if you guys think that will work.

 

[keninaz]

Re: Adding a second Alt batt combo to 3.0L

Too much power for a boat in my opinion.
Just don't park it next to me.

 

[rlcate308]

Re: Adding a second Alt batt combo to 3.0L

My buddy has a pontoon and his idea of a quality sound system is somewhere between a victrola and an old Mustang tape deck with audiovox speakers. I feel I have a moral obligation to provide the toons in our party cove. I plan on posting pics of the boat as it starts coming together. Thanks for the advice.

 

[Jerryh3]

Re: Adding a second Alt batt combo to 3.0L

I was also worried about my stereo running down my single battery. So, I'm moving all of the house loads over to a group 31 deep cycle with a BattCom battery combiner and keeping the existing group 24 deep cycle just for a starting battery.

 

[chrclo]

Re: Adding a second Alt batt combo to 3.0L

If you really want a second alternator I would just replace the one you have with a good quality marine unit with 150amps or so. Your alt now is likely putting out 50-60 amps. The dual batteries are a must for this system. I have never used Boss equipment (I use Kicker, JL, etc) but I would expect the amplifiers to be power hungry.

 

[98Shabah]

Re: Adding a second Alt batt combo to 3.0L

I'm a bit more lazy.. I lacked the space to add a second battery to my 18' Mariah (or at least i didn't want to give up any space), so "just in case" the boat battery gets drained to far down I carry a 750 portable jump pack.. Then during the winter the jump pack lives in the trunk of my car.

 

[fishrdan]

Re: Adding a second Alt batt combo to 3.0L

If you really want a second alternator I would just replace the one you have with a good quality marine unit with 150amps or so. Your alt now is likely putting out 50-60 amps.

I don't see why he needs a second alternator, the stock 50-60 amp alt with recharge the deep cycle safely while running around, probably push 40+ amps while running around. Put a big 100+ amp alternator on the engine and he will be throwing a very high charge current at the deep cycle, unless he's running thee engine slow. 70-80 amps is too high of a charge rate.


I have a 100 amp alt on my boat for charging up 2- group 29's trolling motor batteries and worry that I'm hitting them too hard while charging off the engine, but it's worked fine so far. I'm usually charging them up at low speed, less than 1000rpm, so the alternator isn't delivering it's max output.

I think an ACR would be the best option, keeps the stock alternator, keeps the batteries seperate, but allows the deep cycle to charge when the engine is running.