Alternator upgrade for I/O 4.3 V6

[wildthing]

Hi folks
due to all the electronics and riggers along with music
think i need to upgrade my main engine alternator to a much higher amp output
thinking maybe 120 amp or even a 200 amp
as the kicker is not going to keep up so needing a lot more when the main is running to put some power back into the house battery running two one house one main/start.

have a kem kodiak 4.3l V6 4bb

 

[Wild Bill]

I don't know what they consider a marine alternator and an automotive alternator. Some brush type marine alternators I have worked on had spark screen and some did not. Look at getting financing if looking for a high capacity marine alternator lol! If being marine doesn't matter to you lots of choices however you are still limited by what type of drive you have. Do you have single or double v belt or multi v (often called serpentine but not always configured serpentine)
60 amps is pretty much reliable max with a single v belt. To start looking you just need to figure out the alternator frame type.

 

[ericl]

www.balmar.net

Not all battery types will charge at the high rates a H/O alternator can provide. AGM batteries charge the fastest. Stock alternator is probably around 30A. Balmar has neat stuff.

 

[Rockfish]

There are alternatives as Kickers have different outputs. My new Yami 9.9 HT only puts out 6 amps, but the old one put out 10 amps and some of the 15 hp kickers put out 15 amps or more. If you are like us we are only using the main and its 60 amps for a short time to get to the fishing grounds and back, but are on the kicker for many hours.

You can augment your charging by keeping your battery bank charged up at home or at the marina with a marine rated smart charger (ours is permanently installed and just needs to be plugged in to 120). Some solar cell banks on the cabin roof can add a few amps to the batteries, even in cloud and they can be run through a smart regulator so they do not over charge the batteries.

If its a concern there is always amp conservation. Convert you running lights, anchor light, cabin lights. and flood/spot lights to LED’s and stick with the regular speed riggers as I recall the high speed riggers pull several times more amps.

 

[Fixit]

What do you have for battery's? Single? Dual? Add a battery kit?

I'd say I'm heavy on the dc useage, substantial stereo and sub with two amps, prawn puller Scotty downriggers plotter etc etc
I charge with a stock 70 amp alternator (serpentine belt) and the t9.9

I'd be very surprised if your actually using close to the full output of the alternator (other than just after startup of your main)

 

[Fixit]

Take you average stereo 4 channel 50watts per channel stereo. 200w total
200w/13.8v= 14.5amps
That would be at max volume with a full range signal
I'd guess your probably not cranked up so loud that your speakers are distorting and ears bleeding... let's say your at 5/10 volume

That would be averaging less than 7 amps

Subwoofer. Let's guess that your 1500w (peak) sub is actually getting 500w rms from your amp (that would be an insanely loud sub)
500w/13.8V=36 amps
if you consider that your listening at half volume and the beat (on off on off) I'd be surprised if your averaging more than 10-15 amps

Your Scotty 1106's draws 8 amps pulling a 15 lb ball for maybe 2 minutes every half hour or so?



So even if your sub/amp was melting down, your stereo was blowing up speakers left, right, and center and you were cranking up two 15 lb balls all at the same time you would be drawing 66 amps.... how long do you want to keep that up for? A stock alternator will keep up with that draw all day long

 

[wildthing]

will get details on the batteries i have
but what seams to really hit the voltage drop on my set up is the VHF radio
also i am running 3 MFD's now and 1 k transducers BSM-2 along with a sonichub so if my old system was struggling
sure is going to now
have an older 9.9 yamaha square back kicker
also added auto pilot pump in the mix as well
and 3 scotty std riggers
should i even consider going 6v batts on the house side????

 

[Hookin'up]

Holy crap John, when do you find time to watch the rods

 

[Rockfish]

Good chance your old Yami kicker is putting out 10 amps instead of 6 amps like the new ones so you could be ahead of the game – look up its specs.

I think we are likely close to you in amp draws and are not having problems. We are currently running two Marine/RV batteries with 1000. marine cranking amps and 180 reserve minutes each which is a downgrade from what the guide who had the boat before us was running at 1300 cca and 220 reserve minutes x2 batteries. With the big Opti being a power hog for starting, we use batteries that are more on the starting battery side of the range as opposed to the deep cycle end of the range.
What are you running for batteries?

 

[GLG]

I wonder if putting one of these into your circuit would work?
http://www.ebay.com/sch/i.html?_nkw=supercapacitor+12v

 

[ericl]

All the above advice is great & right-on; doubt you need any upgrades. A deep cycle battery is designed to draw down to 50% of capacity without causing premature failure. BTW charging a deep cycle batter with an automotive style voltage regulator (meant for charging starting batteries) will cause premature failure of the deep cycle. So you'll probably replace the deep cycle every 3 years instead of every 8-10 years. 6 volt Golf cart batteries were the best option for large capacity 40 years ago. I have a 33ft boat with all the stuff you have plus electric fridge & stove. Here is what i have:

Twin engine, Balmar 120 amp alternator on each. Balmar external voltage regulator on each, set for a 3 phase deep cycle charging cycle. Balmar centerfielder to balance/combine output of both alternators. Two Lifeline 8D AGM deep cycle batteries. Balmar duocharge DC-DC charger that charges the starting battery from the deep cycle battery. Group 34 starting battery
Bluesea 120v AC charger hooked to the deep cycle's.

My system is somewhat idiot-proof. I started operating a drill press & other machinery for my Dad at age 12 & was a Marine engineer on a commercial boat at age 17. I realize that others who may want to use my boat do not have my skillset.

 

[wildthing]

cheers ericl
looks like a need a fishing buddie like you to come sort my system out .....
but i do need to renew my batt's especially the house one
and fit the si -acr i did have a older solid state RV relay with a 3 battery set up
but was never sure if it worked right

my alternator is a twin belt 70A output 1665 was the only numbers i could make out on it ?

 

[ericl]

Hi wildthing. Glad to help; just let me know what you want.

That alternator should be fine. Most of the time the music will be drawing 1 amp or so, same for the electronics.

The Balmar regulator is $369 US. The DC to DC Charger is $259 US (I live in the states). The other option is to leave your system as-is & just replace the house battery more often. The Balmar stuff is targeted at long range cruisers who don't want the house battery to fail on a multi-day trip (inconvenience) You can buy a AC powered charger for the house battery & give it a proper charge back at home.

Let me know how I can help, Eric

 

[Wild Bill]

Cool stuff! Just wondering how you delete the built in voltage regulator? The dc to dc charger would work great in all sorts of applications, rv etc.

 

[ericl]

Cut the wires.