Generator Head?

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janice142

Guru
Joined
Oct 12, 2011
Messages
1,238
Location
USofA
Vessel Name
Seaweed
Vessel Make
Schucker mini-trawler
So Betsy, my Kubota 18hp diesel runs like a dream. She's practically perfect in every way.

And I've been thinking. Wouldn't it be nice to have my little 18hp engine supply power to the boat via a generator head. I found one for $300, and it's got me twitching.

Specifically, I like this one:
NorthStar Generator Head — 4500 Surge Watts, 4000 Rated Watts, 9 HP Required, J609B Engine Adaption | Generator Heads| Northern Tool + Equipment

NorthStar Generator Head — 4500 Surge Watts, 4000 Rated Watts, 9 HP Required, J609B Engine Adaption

NOT when underway, but at anchor, what say the experts?
Know this: the maximum my engine might burn is 1 liter per hour. A friend has this identical unit in his tractor and at 1700 rpm burns 1 liter in two hours.

Idling I should do about the same, shouldn't I?

I've not burned one gallon yet though I've only run her for five hours so far. That's all at the dock so I've not got any underway figures.

So, what precautions should I take? Anything specific?
The long-liners use bigger ones and they run for six weeks at a time 24/7 without issue.

Thanks.

And yes, you may celebrate with me. Betsy is AWESOME. Life is wonderful. I am blessed.
 
I'm assuming you would direct couple it like it says in the manual to the front of your motor? From the online manual, you need to spin it at 3,600 RPM to get power (less won't give you the correct voltage). Not sure how many hours it will live as every time you run the boat, you will be spinning the generator. Before I went any further, I would run Betsy up to 3,600 RPM and see how noisy she is. You may also find she puts out a fair amount of heat.

Sorry for throwing water on your fire. :hide:

Ted
 
By the time you fabricated and codged together the mechanical connection and came up with a governor to keep the engine RPM constant, and the elctrical sircuitry to feed the boat, I'd guess one would be better off and much more simple getting another alternator and using Betsy as a DC generator. The item pictured is designed as a direct replacement for the heads certain gas operated generators.

I know it's maybe the worlds worst web site, but take a look at ZRD and give them a call, they are really expert on what you want to do:
http://zrd.com/faq/esdfaqwdcgs.html
ZRD Electric Designer OEM - Your Source for DC Generator, Alt, ...

By the way, your engine will not be at idle, as Ted noted, and it will be under load increasing the more you power demands you put on it.
 
I used one similar but a 12KW that was PTO driven on my 27hp tractor. Worked fine but was very rpm sensitive. Basically had to adjust the throttle to get the Hz at 60. Each time a big load such as air conditioner came on the Hz dropped a bit so had to either re-adjust throttle or set Hz a bit higher to compensate.
Probably be easier to use alternator as suggested.
 
I'd guess one would be better off and much more simple getting another alternator and using Betsy as a DC generator.

Yup! An alternator and a battery and you are making DC current. Add an inverter and you have AC. Voila!


I suspect Betsy already has an alternator? Might be sufficient as is? If not, maybe just increase the size of the existing alternator? Direct battery charging, without needing another AC source (genset plus charger) in between? Maybe beef up the battery bank? Seems a lot easier/cheaper than trying to regulate RPMs...

Inverter for AC loads (microwave, TV, etc.) still not too expensive...

-Chris
 
I head about something similar several years ago. The boater could operate his 120 volt AC unit by idling the boat's engine at 1000 RPM or so and of course it would also work while underway. There was an additional (large) alternator attached to the engine with an additional belt and an inverter/regulator to convert the output to 120 volt, 60 Hz AC.


I looked into it and the company was out of business. That tells me something. That and the fact that few people had ever heard of the option.


I think you're going to need some way to regulate the voltage and frequency of that unit and the fact that there's only a three month warrantee speaks to the quality.
 
A large alternator would be the better choice.

A rapid recharge of the house and no specific RPM to get 120V at 60cps.

A 2000W RV or truck inverter ( $150 or so) will do most things short of BIG Electric, air cond water maker or scuba refill , loads .

If you want air cond DC is still the best choice , but may require caution as most lawn equipment is not rated to take heavy HP out the front end.

http://www.amazon.com/s/?ie=UTF8&ke...vptwo=&hvqmt=b&hvdev=c&ref=pd_sl_6qofqywlqp_b

What 120V stuff do you want to operate? When ?
 
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Second above guys advocating for DC alternator to batt bank to inverter.

You may not have much of a DC alt on that Kubota now, that could be a good upgrade. But not easy to mount as it is not a very big engine to start with and a big alt takes up a lot of room. Maybe mount alt backwards, pulley end toward engine.
 
Thank you Gents... I'd wondered about the generator heads. My thought was that because Betsy uses so little fuel she could be running by boat with ease with power to spare. The regulating hz part I missed entirely. Thank you for that knowledge. It is critical.

Betsy's alternator was a toy. It put out 5 amps.

I've now got a Hurth 55 amp mounted. That is spiffy as all get out. When I run across an external regulator for it (has been wired for same) I'll attach that. In the meantime the internal is doing the deed, just not as efficiently as it could be.

My boat runs off 12 volts. I was trying with the generator head to "beat the system" and have a way to run an a/c (Haier 5k btu wall-banger that uses 455 watts) at anchor on those steamy summer days or when the mosquitoes are particularly vicious.

I've got an inverter (1200 watt, pure sine wave)

Between house and start banks Seaweed has 700 amp hours available. Yes, I run on "Both" as a general course.

Power generation via solar (455 watts) and wind (Air Breeze) and engine alternator (55 amps)

Power wise, my boat is fine EXCEPT for the a/c unit. I cannot run that while anchored. Figuring out how to make that happen is the dilemma. It was on the back burner until I heard the long-liner's raving about their generator heads. For a $300 or $400 price tag, it moved right up front. :)

Alas, unless there is a way to solve the issue with throttle adjustments... well, I just cannot see this as right for me. I certainly don't want the a/c to run cold all the time. I like it to cycle off.

Such is life onboard Seaweed. If there is a way to do this for $300 or $400 I'm interested. I saw the warranty was for three months. For $35 more it extends to 15 months.

A Honda would be $1000... there are other things that will take priority before a Honda, or a Yamaha. I like the Yamaha's too.

Anyway, thanks for bursting my bubble. I do appreciate your collective wisdom, and was hoping for a solution that was affordable. Especially since many Kubota's are actually generators. Mine is a propulsion system however ... well, I was wishing.
 
And Ski... the alternator is wired with a switch. I only turn it on once the engine is running. The mechanic was concerned that there might be a situation where I needed all 18hp that Betsy has. Thus, I can shut down the alternator with that switch.
 
A large alternator would be the better choice.

A rapid recharge of the house and no specific RPM to get 120V at 60cps.

I don't understand 60cps. ??
 
Thank you Gents... I'd wondered about the generator heads. My thought was that because Betsy uses so little fuel she could be running by boat with ease with power to spare. The regulating hz part I missed entirely. Thank you for that knowledge. It is critical.

Betsy's alternator was a toy. It put out 5 amps.

I've now got a Hurth 55 amp mounted. That is spiffy as all get out. When I run across an external regulator for it (has been wired for same) I'll attach that. In the meantime the internal is doing the deed, just not as efficiently as it could be.

My boat runs off 12 volts. I was trying with the generator head to "beat the system" and have a way to run an a/c (Haier 5k btu wall-banger that uses 455 watts) at anchor on those steamy summer days or when the mosquitoes are particularly vicious.

I've got an inverter (1200 watt, pure sine wave)

Between house and start banks Seaweed has 700 amp hours available. Yes, I run on "Both" as a general course.

Power generation via solar (455 watts) and wind (Air Breeze) and engine alternator (55 amps)

Power wise, my boat is fine EXCEPT for the a/c unit. I cannot run that while anchored. Figuring out how to make that happen is the dilemma. It was on the back burner until I heard the long-liner's raving about their generator heads. For a $300 or $400 price tag, it moved right up front. :)

Alas, unless there is a way to solve the issue with throttle adjustments... well, I just cannot see this as right for me. I certainly don't want the a/c to run cold all the time. I like it to cycle off.

Such is life onboard Seaweed. If there is a way to do this for $300 or $400 I'm interested. I saw the warranty was for three months. For $35 more it extends to 15 months.

A Honda would be $1000... there are other things that will take priority before a Honda, or a Yamaha. I like the Yamaha's too.

Anyway, thanks for bursting my bubble. I do appreciate your collective wisdom, and was hoping for a solution that was affordable. Especially since many Kubota's are actually generators. Mine is a propulsion system however ... well, I was wishing.

Again, I would encourage you to read the links I posted and to give ZRD a call and discuss with them. This is right down their alley.
 
Janice: what about a small gas Honda genny? They're quiet, don't use much fuel and they'll easily power your A/C unit. Plus, they're smart-they adjust for the loads, and they're pure sine.


Jim
Sent from my iPad using Trawler Forum
 
Janice, oh by the way, congrats on getting that Kubota up and running. I know there were bumps in that road!!!
 
Again, I would encourage you to read the links I posted and to give ZRD a call and discuss with them. This is right down their alley.

Thank you. I did give a look see. At a base price of $6300, that is well out of my realm. It was an interesting read -- just not for me.

Thanks though for posting as I'm sure many others might consider it. Both pages are informative.

Janice: what about a small gas Honda genny? They're quiet, don't use much fuel and they'll easily power your A/C unit. Plus, they're smart-they adjust for the loads, and they're pure sine.

As a matter of fact I have considered one Jim. Not for this year however as a down the waterway thing? Yes. Ideally I'll find a solution that allows me to keep with diesel.

For $300 or so, this might have been a solution. Not for you guys with the big fuel consuming engines. Mine though sips diesel so I'll be exploring a bit further.

In the meantime with the solar now in place my life is exactly the same rather I am at a dock or anchored in the middle of nowhere. I like that.

Janice, oh by the way, congrats on getting that Kubota up and running. I know there were bumps in that road!!!

Several of those bumps were the size of Mount Everest, however all is well now. I could not be happier.

I am so blessed. A huge well of gratitude to those who supported me during the trials. The information offered was Very helpful in getting a solution that works.

Seaweed is a terrific boat -- just perfect for me. Truly I have the best boat ever. You cannot imagine how nice it is to live aboard my Seaweed.
 
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I know that truckers have a/c units designed to run on batteries. Has anyone here ever investigated those units for marine purposes?
 
I know that truckers have a/c units designed to run on batteries. Has anyone here ever investigated those units for marine purposes?

I believe Dometic has DC units that are about 3500 BTU

This would be fine underway but the batt bank for O nite would be too large for a small boat.

Then of course is dock side how do you create DC to run the unit from 120VAC?

Needed is at least 30Anps plus what ever house and batt recharge loads exist.

http://www2.dometic.com/bd10b370-ad73-44f7-a491-9d1459e03737.fodoc
 
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Janice, a larger inverter may start your small AC, and if so the load would reduce after that. Then you might be able to run it for useful periods with Betsy running. Buy larger and sell your current inverter?

Check out you AC start/run specs to see if feasible...
 
The idea of airconditioning is nice isn't it? This normally means closing doors and windows which makes the noise of a diesel generator that much more intrusive. Is sound insulation on Seaweed good enough that you and Betsy could happily coexist in close quarters?
 
Found something interesting. A 2,000 BTU a/c unit for truck cabs that runs on batteries. Looks like a split unit. There is a link to a video on this page:
Jackson Truck and Trailer, Inc.

Interesting...
I did not check pricing however, as a reference:

In 90 degree weather with the sun baking my boat I use a 5k btu Haier. She has settings 1 through 10.

I set her to cycle on and off (she doesn't go off much when it's midday!) and 3 generally works. Sometimes I have to move up to #4. That puts the inside temperatures in the mid to upper 70's -- comfortable without being cold. I do not do cold.

Main cabin size 7' by 11 feet including area in front of helm. There are a LOT of windows and she's a bit drafty too.
My cabin is 8' long and narrows at the bow.
Insulation in Seaweed is nonexistent.

5000btu is more than sufficient when placed in the pilothouse door. When in the hatch in my forward cabin the main cabin did not get cool. Didn't work there.

Eventually (soon!) I'd like to mount it on the roof in my galley. I've got the scoop to do it nicely and will move the fan-tastic fan forward to my pilothouse. One step at a time, don't 'cha know?!?

I believe Dometic has DC units that are about 3500 BTU

http://www2.dometic.com/bd10b370-ad73-44f7-a491-9d1459e03737.fodoc

Uses 29 amps. Sometime to consider however Dometic will definitely be lots more expensive than my already bought $130 Haier. And I've seen a lot of room a/c units (house type) on boats. They can be mounted so as to look quite alright.

Janice, a larger inverter may start your small AC, and if so the load would reduce after that. Then you might be able to run it for useful periods with Betsy running. Buy larger and sell your current inverter?

Check out you AC start/run specs to see if feasible...

My current inverter is 1200 with a peak at 2400 watts. A/C unit takes 455 watts when running.

I did learn a trick on how to start stuff that is "too much" for the inverter. First. you plug in what you want to run, THEN power up the inverter. That will work in some applications as long as the running wattage is within specs.

Anyway, just putting that out here in case you need another bullet in your arsenal. :)

The idea of airconditioning is nice isn't it? This normally means closing doors and windows which makes the noise of a diesel generator that much more intrusive. Is sound insulation on Seaweed good enough that you and Betsy could happily coexist in close quarters?

I thought of that. When running the anchor chain rattles. You know, at anchor I never hear it. That's the sound of sleeping well because I'm secure.

The Hella fan right by my ear was dreadful until the temperature and humidity went up. Then suddenly it was not too loud at all.

Betsy with the hatches open is loud. Closed though is much better -- conversation is possible and I can even hear the VHF radio. I could and would do more to insulate the sound but even today it is Good Enough.

What I would miss is life outside. I am well aware that those boats that stay closed up miss some of the best parts of life out here: the wildlife, nature, dolphins and manatees, etc. When it's 90 degrees out there and the humidity is higher I am FAR less interested in wildlife than when it's cooler!
 
I think a large DC alternator, maybe additional pulley on Betsy's crank, all running through your batts and inverter could easily run that 500W AC unit, with engine set at maybe 1500rpm.

It's do-able.

When I stayed on my ride in Fla, I could close up the boat an hour before bed and run the gen and AC hard, it would chill and dry out the boat. Then turn it all off. It was good sleeping til the sun came up. That sunshine with no AC on is a very effective alarm clock!!
 
I am definitely in Ski's camp on this one.
Only, I am questioning a 5k BTU AC unit that only draws 450W. seems to me it should be twice that at least.

Though it costs some dough, a good sized alternator with ample batteries and a good 2500W inverter provides a lot of performance and flexibility as well, since you already have wind and solar power to supplement the alternator.
 
Janice-first-glad to hear that Betsy is up and running and that Seaweed not only floats but is mobile! Have you looked either on Amazon or Ebay for portable gennies? Just a quick look a minute ago showed 1000 watt units anywhere from $250 to about $900. Since the only thing you really need it for is the AC, you could have the genny on deck with the AC wired directly to it. It seems you only really need it a few hours a day. As has been noted, the new portables are pretty quiet.
 
I am definitely in Ski's camp on this one.
Only, I am questioning a 5k BTU AC unit that only draws 450W. seems to me it should be twice that at least.

Could be about right. My forward a/c unit is 9k and according to my Kill-A-Watt it consumes 6.8 amps at 115 volts or about 780 watts.
 
My 6,000 btu runs at 3-4 amps with a bit of a surge when the compressor kicks on...but that is very instantaneous...probably fast enough to not trip a breaker of 5 amps.
 
My 6500btu/hr Mermaid with water pump draws about 6-7A on 120V. Sounds like all of them are in the ballpark. Mine does not sound terribly efficient. But it works.
 
I was not including the pump draw...but that is minimal if sized to only a 6000btu unit.
 

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