Maybe stupid question...

tramsdell

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Good morning! I was thinking about ways to charge my trolling batteries on extended off grid outings. Seams a generator and batt charger would be the way to go. My thought was an on board charger, and run that off a cheapy 2 stroke generator. I could make a mount for the trailer tongue, or just throw it in the trunk, but then i thiught about locations where the boat is moored off and considered making a temporary as needed mount for the generator in the splash well of the boat. Now my question: is it possible to plumb a fuel line from the boats tank, and have it run a generator? Initial thought is no because the generator has no fuel pump, but in poking around the net it seams that peple are using marine tanks to extend generator run time.
 

Scott Danforth

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remember, the exhaust from that generator will fill the boat hull up with carbon monoxide. I wouldnt run it in the boat. I would run it away from the boat. I also wouldnt play with the fuel system on them as most are gravity fed.

a set of jumper cables and your truck running for 45 minutes would charge the battery just fine.
 

H20Rat

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a set of jumper cables and your truck running for 45 minutes would charge the battery just fine.

Vehicle alternators, especially GM's, produce almost no power at idle. I've seen decent size stereo's actually drop the battery of an idling vehicle before. (ie, they are lucky to produce 20% of their power, so if you have a 100 amp alternator, you get 20 amps, and a idling fuel injected vehicle is going to take at least 15 of those with all accessories shut off) Trying to recharge a big deep cycle with an idling alternator can even kill it, you get lots of heat buildup without much air movement.

Anyway, to the OP. Avoid 2 stroke generators at all costs. They suck. Their voltage is nearly unregulated, it will swing from 90 volts to 150+ volts. I would never plug in any device except for a light bulb in one of those. (and yes, I've owned several) They also sound like a chainsaw held at wide open throttle, because that is essentially what they are.

If remote charging is your only option, get a honda generator. Anything else is just a temporary step and will cost you more. And do NOT try to mix it into your boat fuel system. That is just a recipe for kaboom.
 
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Alumarine

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Some of the 4 stroke generators also have 12 volt charging ability that might eliminate your need for a separate charger.
 

gm280

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Sounds like a small self-contained 4 cycle portable generator would fit the bill. Quiet, runs long enough to change your batteries and has it's own fuel tank. A win, win, win to me if I were going to do such a thing. :decision:
 

Scott Danforth

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Vehicle alternators, especially GM's, produce almost no power at idle. I've seen decent size stereo's actually drop the battery of an idling vehicle before. (ie, they are lucky to produce 20% of their power, so if you have a 100 amp alternator, you get 20 amps, and a idling fuel injected vehicle is going to take at least 15 of those with all accessories shut off) Trying to recharge a big deep cycle with an idling alternator can even kill it, you get lots of heat buildup without much air movement.
.

good to know, I need to go back in time to tell our family it wont work, even though its been in practice for over 45 years that I am aware of.
 

tramsdell

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remember, the exhaust from that generator will fill the boat hull up with carbon monoxide. I wouldnt run it in the boat. I would run it away from the boat. I also wouldnt play with the fuel system on them as most are gravity fed.

no worries there, im talking about outside on the splash well, like near the transom.

a set of jumper cables and your truck running for 45 minutes would charge the battery just fine.

my disagreement aside, many spots wouldnt be accessible by vehicle, 1 spot in particular the boat cant really come to shore, has to be moored some distance off.



so, probably best to use the small gas tank on the unit, and wade out with more fuel?
 

tramsdell

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Some of the 4 stroke generators also have 12 volt charging ability that might eliminate your need for a separate charger.


i looked into those but it seems at the lower price point the chargers built in are kinda crappy, and if it was its own separate charger i could plug it in at home as i do now. This is just a solution im coming up with for extended stays in the Bush. Nothing permanent, im just trying to eliminate jerry cans from the supplies lol.
 

tramsdell

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Vehicle alternators, especially GM's, produce almost no power at idle. I've seen decent size stereo's actually drop the battery of an idling vehicle before. (ie, they are lucky to produce 20% of their power, so if you have a 100 amp alternator, you get 20 amps, and a idling fuel injected vehicle is going to take at least 15 of those with all accessories shut off) Trying to recharge a big deep cycle with an idling alternator can even kill it, you get lots of heat buildup without much air movement.

Anyway, to the OP. Avoid 2 stroke generators at all costs. They suck. Their voltage is nearly unregulated, it will swing from 90 volts to 150+ volts. I would never plug in any device except for a light bulb in one of those. (and yes, I've owned several) They also sound like a chainsaw held at wide open throttle, because that is essentially what they are.

If remote charging is your only option, get a honda generator. Anything else is just a temporary step and will cost you more. And do NOT try to mix it into your boat fuel system. That is just a recipe for kaboom.

I like the honda suitcase generator idea, i may go that route.


Also, I'm not trying to mix into the boats fuel system, i could add a second pickup to the tank, second line, with shutoff valves etc. But the question becomes: will it send fuel uphill ? Do the honda suicases have a fuel pump on them?
 

tramsdell

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Depending how much charging you're talking, those small inverter gennies run a long time on one tank in eco mode. If you can charge your batteries in a couple hours, you'd get several days on one tank of gas.

Alternatively, a cheap siphon pump and you can get gas out of the boats tank when needed.

This. I didnt know how efficient these lil buggers are. Charging my trolling bank takes about 6 hrs, so should easlily manage that in one tank?
 

roffey

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I likely should not jump in here as I really don't know what om talking about, lol, but.... could a solar panel work? that way your constantly charging and no gas to worry about. I have a electric boat lift and my deep cycle battery is charged from a solar panel and so far no problems.
 

tramsdell

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I likely should not jump in here as I really don't know what om talking about, lol, but.... could a solar panel work? that way your constantly charging and no gas to worry about. I have a electric boat lift and my deep cycle battery is charged from a solar panel and so far no problems.

Thanks for the suggestion, but i can't rely on sunny days and i think it would take a very long time to recharge. I use the trolling motor A LOT.
 

tramsdell

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Unless you have a massive 100 amp charger, it would be no problem running for 6 hours on one tank.

Nice, i checked around and it looks like a suitcase genny specs at 15lb so i dont mind wading out with that at the end of the day. Beats the crap outta unbolting batteries and carrying them all in and out! And as stated i can just siphon gas outta the boat if i find Gerry cans too annoying.
 

KD4UPL

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The Honda 1000 watt gen. should be big enough, or you could use the 2000 watt, it's not much more money. Either will run probably around 8 hours on a tank just charging a battery. Don't bother with the "built in" 12v battery charger on the generators. It is very low output and unregulated so basically useless. You will still need a good 120v AC charger to plug into the generator.
As much as I like solar power I don't see it as a realistic option here. It doesn't sound like you have the room or the patience for it.
 

QBhoy

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Few friends with cruisers have a 4/ 1000kva genny connected to a proper marine exhaust pipe out through a skin fitting in hull. They used the Eberspacher type exhaust pipe and stainless skin fitting.

1000kva genny is fine for most things other than any real serious heat type application like a household kettle or heater. Many think these generators rated at 1000kva mean 1000 watts. They aren’t. Usually only about 800-850 max. So will struggle to run your average household microwave...but everything else is ok. Your average kettle will be 1500-1800 watts. So they are out.
 

Lowlysubaruguy

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Buy more batteries. I carry six when I go camping. Generators unless really big take many hows to charge a pair of deep cycle batteries. The generator that will do this job in say four hours weighs about what 6 batteries does any way and costs about 6 times more money. And you need gas. Myself I hate the noise and do not welcome them into my camp. I’d image four to 6 hours of one of them running where your boating would begin to drive most people nuts as welll.

But that’s just my two cents worth.

I also have a very short custom made battery cables that I do boost my campers batteries when I have the opportunity like lunch or when we get back from a hunt and I dont mind having a truck run for 20 to 30 minutes the heavier the better. The longer a cable is the more power is lost in its transfer so short and heavy..
 
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