Is it ok to run generator while cruising

lprizman

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Re: Is it ok to run generator while cruising

with proper ventilation should be no issue
 

H20Rat

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Re: Is it ok to run generator while cruising

That is the BEST time to use a generator! Its often unsafe to use one while anchored, depending on generator setup and wind conditions.
 

JoLin

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Re: Is it ok to run generator while cruising

Agree with smokingcrater as to the safety aspect, but... why would you need it when you're underway? Not to charge batteries (engine alternators do that), not to run the A/C (you'll burn out the unit if on plane and the water pickup isn't buried), not to run microwave, electric stove, coffee pot or 'mudslides' blender (it's unsafe to use appliances underway).

Only bringing this up because the OP is new to the boat, and I'm a little curious as to why he would need to use it underway.
 

shrew

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Re: Is it ok to run generator while cruising

Is this an onboard generator? Or are we talking about a portable generator. If this is an onboard generator with a through hull pickup and either raw water or cloed cooling then it's perfectly fine to run either while underway or at anchor. If this is a portable generator, then no it is not a good idea to have it running while underway. I assume this an an onboard generator.

Onboard generator use a water cooled exhaust and discahrge both exhaust and cooling water overboard, so ventilation is not an issue. This is not the case with a portable. As far as safety goes, a portable would NOT be safe while underway, on anchor it is fine, provided it is properly ventilated, such as tied to the swim platform.

Onboard generators can run 110V devices such as A/C, Heat, Freezer, Fridge, hot water heater, and battery charger. This can reduce the amp hour draw on the house battery bank for 12v devices as well, even while underway.
 

JoLin

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Re: Is it ok to run generator while cruising

Onboard generators can run 110V devices such as A/C, Heat, Freezer, Fridge, hot water heater, and battery charger. This can reduce the amp hour draw on the house battery bank for 12v devices as well, even while underway.

I don't have a genny, but many of my friends do, and running it while underway isn't a common practice. There's nothing on that list that can't be serviced just as well by the engines' waste heat (water heater) or the alternators, which charge the batteries at a higher rate than any of those appliances can discharge them. And on my boat, the A/C thru-hull water intake would be out of the water if I was running at planing speed.

I'm just debating this with you. I don't see the point of using the genny and additional fuel to do what's being done by the engines anyway.

My .02
 

shrew

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Re: Is it ok to run generator while cruising

My A/C has a running pickup and is all the way back by the transom and about 1/2 between the keel and the reverse chine. It would pickup water on mine just fine when running. The Genny pickup would also need to be a running pickup and located far astern and low enough to pickup water while running. I agree, not common, unless your a yacht or large fishing boat. The altenator charges the starting battery, not the house battery bank. Genny or shore power charge the house battery bank. That is unless you start and run the motor on the house batteries.

BTW_ I never said it was commonly practiced, however common and posible are mutually exlcusive topics here.
 

Thalasso

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Re: Is it ok to run generator while cruising

I don't have a genny, but many of my friends do, and running it while underway isn't a common practice. There's nothing on that list that can't be serviced just as well by the engines' waste heat (water heater) or the alternators, which charge the batteries at a higher rate than any of those appliances can discharge them. And on my boat, the A/C thru-hull water intake would be out of the water if I was running at planing speed.

I'm just debating this with you. I don't see the point of using the genny and additional fuel to do what's being done by the engines anyway.

My .02

If your boat had a jenny, the builder would have put the water intake at a point on the hull where that wouldn't happen. I am sure the your hull is in the water at some point.
 

rbh

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Re: Is it ok to run generator while cruising

I am betting with all the gadgets the OP may have on board his "33 footer" IE electric stove/BBQ, ice maker, TV, home sterio, microwave, blender ETC, it would be nice to have some AC power, as 12vDC aint gonna cut it (even with a converter)
And I do not agree with "not" using your appliances while cruising, as long as your in good weather and not piloting the boat at high speeds.
(as was said your genset must be able to operate underway)
OH do I wish we had a built in Gen set!!!! :D
 

JoLin

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Re: Is it ok to run generator while cruising

If your boat had a jenny, the builder would have put the water intake at a point on the hull where that wouldn't happen. I am sure the your hull is in the water at some point.

I was talking about the water supply for the A/C, not the genny. Yes, if I had a genny, it would be near the stern, and so would the water intake for it.

Shrew, I get it. Surprised yours is fitted so far aft. My A/C seacock is directly below the mid-cabin, along with the seacock for the head, and would be out of the water or sucking 'spray' if I were on plane. Also, I have a Perko switch on my boat, so I can charge whatever combination of batteries I want to off the engine alternators. I'm sure the OP does, too.

rbh, I'm not opposed to using appliances at low speed in good weather, either, but the OP was asking about running the genny when 'cruising', which is a pretty broad term. A 33' Sundancer isn't a trawler- typical cruising speed for the OP will be something like 25 mph. So, I'll stick to my opinion that running the genny when cruising isn't typical, and there's generally no reason to use it when the engines are providing all the power needed.

Enough of this frivolity- bring on the the dancing girls!
 

Thalasso

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Re: Is it ok to run generator while cruising

I was talking about the water supply for the A/C, not the genny. Yes, if I had a genny, it would be near the stern, and so would the water intake for it.

Shrew, I get it. Surprised yours is fitted so far aft. My A/C seacock is directly below the mid-cabin, along with the seacock for the head, and would be out of the water or sucking 'spray' if I were on plane. Also, I have a Perko switch on my boat, so I can charge whatever combination of batteries I want to off the engine alternators. I'm sure the OP does, too.

rbh, I'm not opposed to using appliances at low speed in good weather, either, but the OP was asking about running the genny when 'cruising', which is a pretty broad term. A 33' Sundancer isn't a trawler- typical cruising speed for the OP will be something like 25 mph. So, I'll stick to my opinion that running the genny when cruising isn't typical, and there's generally no reason to use it when the engines are providing all the power needed.

Enough of this frivolity- bring on the the dancing girls!

The question was . (quote) New to boat and am wondering if its ok to run generator while cruising. (unquote)

My response was to the question and to your response about being on plane
 

Jlawsen

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Re: Is it ok to run generator while cruising

I'm a little confused about these responses. The 33' Sea Ray I was on had house batteries and a GenSet. The generator came on automatically when the house load exceeded the battery capacity or if the batteries charge level reached 40%. The engines alternators ran the normal underway equipment and kept the starting batteries charged. It ran in port and underway and was all automatic.
 

Fireman431

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Re: Is it ok to run generator while cruising

Yes, it is OK to run underway with a genset. I am willing to wager that any factory installed raw water intake for genset pickup is the 'scoop' style, which allows water to be pulled in, even on plane. I have seen over 100 large boats out of the water and they have all been equipped with that.

As far as the other poster saying there's no reason to have the genset on, I heartily disagree. While underway, the family can be in the salon with the A/C on, a television/DVD going, food on the stove or in the microwave, the ice maker dumping another batch of ice, and the water in the heater warming up for a shower. None of these items on my boat are 12v powered.

If, in the event that your genset isn't getting enough water while up on plane and/or at speed, then genset will shut itself down prior to any damage being done. Most have 7-9 separate failsafes that will shut it down before toasting itself (low water flow, low oil pressure, insufficient/extreme voltage output, high temp, etc).
 

JoLin

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Re: Is it ok to run generator while cruising

Yes, it is OK to run underway with a genset. I am willing to wager that any factory installed raw water intake for genset pickup is the 'scoop' style, which allows water to be pulled in, even on plane. I have seen over 100 large boats out of the water and they have all been equipped with that.

As far as the other poster saying there's no reason to have the genset on, I heartily disagree. While underway, the family can be in the salon with the A/C on, a television/DVD going, food on the stove or in the microwave, the ice maker dumping another batch of ice, and the water in the heater warming up for a shower. None of these items on my boat are 12v powered.

I apparently didn't make myself clear in my other posts, so I'll try to clarify:

1. CAN the genset be run at any cruising speed? Of course it can. Water intake is likely near the stern of the boat, and fully immersed regardless of speed. No issue there, and I never said otherwise.

2. CAN the A/C (air conditioning) be on at any cruising speed? Depends on the boat. As I stated earlier, if I were on plane and running A/C I'd burn the unit out, as the water intake for the A/C would be out of the water. The OP needs to know where the water intake is on his Searay, but if he has a Sundancer I'll bet it's amidships, like mine.

3. If the OP's boat is an express cruiser ike mine (I assumed he has a Sundancer, but looking back I see he never actually said that), trying to cook or brew coffee at cruising speed (25 mph) would be kinda dumb. OF COURSE he can do so at low speed in good weather.

4. Using TV/DVD or ice maker at cruising speed? Okay, I never thought of that. I have neither. Only the OP can decide if that's a good reason to run the genset, but of course he can with no downside except the costs associated with running a third engine.

My responses were based on my definition of 'cruising' as being 'on plane at 20+ mph', 'cause when I'm cruising, that's how I'm running. That's all. As you guys pointed out, 'cruising' can mean different things.

My .02
 

Fireman431

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Re: Is it ok to run generator while cruising

JoLin, thanks for the clarification, To me, cruising means not anchored. I rarely run on plane anymore, except to clean out the engines or to get past a long, boring area. Burning 45 GPH will take the fun out of being on plane VERY quickly! :eek:
 

sasto

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Re: Is it ok to run generator while cruising

I would run my generator if needed. It is there to be used. Don't use it.....you loose it. There have been issues with some designs while at anchor. Idealy the exhaust would come out of the transom. Not all do. With a solid swimplatform gasses may become trapped under the platform. Swimmers beware while running genny at anchor. If you desire AC power while running.......no worries.

JoLin.....Not knowing which A/C unut you have, but the low pressure switch should shut the compressor off and save the unit.
 

JoLin

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Re: Is it ok to run generator while cruising

JoLin.....Not knowing which A/C unut you have, but the low pressure switch should shut the compressor off and save the unit.

Good to know. Thanks. It's academic in my case as I can only use it when tied to shore power, and I don't have a long enough cordset to do so when cruising


:D
 

JoLin

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Re: Is it ok to run generator while cruising

JoLin, thanks for the clarification, To me, cruising means not anchored. I rarely run on plane anymore, except to clean out the engines or to get past a long, boring area. Burning 45 GPH will take the fun out of being on plane VERY quickly! :eek:

The beauty of a boat like yours is that I'm sure it's a lot more efficient at sub-planing speeds than mine is. Last summer I got hung up behind 2 trawlers in a narrow channel for nearly an hour. They were running merrily along at 9 mph. That's where a boat like mine just falls to pieces- for me to keep up with them I was turning 2300-2400 rpm, and plowing to beat the band.

In my boat, a 50% rpm increase (to about 3500), TRIPLES that speed and I'm using 16(?) gph. I really hate having to run slow, unless it's at idle speed through a no-wake zone. That's where I can run all day at 600 rpm / 4-5 mph burning 1 gph per motor.
 

Fireman431

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Re: Is it ok to run generator while cruising

The beauty of a boat like yours is that I'm sure it's a lot more efficient at sub-planing speeds than mine is. Last summer I got hung up behind 2 trawlers in a narrow channel for nearly an hour. They were running merrily along at 9 mph. That's where a boat like mine just falls to pieces- for me to keep up with them I was turning 2300-2400 rpm, and plowing to beat the band.

In my boat, a 50% rpm increase (to about 3500), TRIPLES that speed and I'm using 16(?) gph. I really hate having to run slow, unless it's at idle speed through a no-wake zone. That's where I can run all day at 600 rpm / 4-5 mph burning 1 gph per motor.

True that. Even tho I have a planing hull, I cruise at approx 1800 RPM, which gives my roughly 10 MPH, depending on wind and current. This burns 6-8 GPH total for both engines. Aside from that, I'm sure I have more room in the salon for the family to hang out while cruising, so all of the 110v stuff gets used a lot more. And we routinely make a day booze cruise with 8-12 people, so the AC and 110v power is a must.
 
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