Genset while underway

[Harbor Nights]

My genset is in the stern as is the pickup for the genset. It has the mushroom pickup and is an Onan 7.5.

What do you all think of a genset running at cruise of say 7-9kts. We would only need this for say christmas lights or maybe baking underway.

We have a twin engine and I was wondering if the prop wash would interfere with the water flow of the genset pickup.

Any suggestions?

 

[Bay Pelican]

Our Westerbeke 8kw is also at the stern. Bay Pelican is single engine and the prop is to the stern of the pickup for the generator. We occasionally run the geneset underway, usually at night. The prop wash does not appear to interfere with the genset's sea water pickup.

Marty

 

[Alex F]

They're designed to run underway. If there was any doubt by the builder you would see a big warning label along the lines "...DO NOT RUN WHEN THE BOAT IS UNDERWAY...." on the genny and in the owners manual. I bet there are no labels. Thus, run it as you need it and enjoy the cruise.

 

[Edelweiss]

I have a 7.5 Onan with the mushroom pickup as well. We don't normally run the gen set while underway, unless we need heat or are using the stove. But up to 10 knots the generator runs nice and cool. Downside to the mushroom intake with no guard is it will suck up debris, eels, eel grass and poppers, so visually check your sea strainer with a flashlight every couple of hours.

 

[Pau Hana]

Shouldn't be a problem unless you're planing

Seriously, we run ours all the time underway with no worries.

Make your life easier- change the electric stove out for a propane one!

 

[psneeld]

no problem unless you suck something up...and then the genset should shutdown before any damage except for an impeller.

 

[magicbus]

Our 12kw Onan has a water flow sensor that shuts it down if needed. We run it when moving if needed without even thinking about it.

Dave

 

[BruceK]

We do it with an Onan 6.5kw, never a problem. The auto protection is there, doubt you`ll need it.

 

[Aquabelle]

Do you turn your battery charger off when running genset underway? To avoid confusing the engine alternators, which would otherwise be 'seeing' multiple charging sources hitting the batteries?

 

[Nomad Willy]

Very good question Aquabelle and I don't know the answer but think it should'nt be a problem.

Harbor Nights are you asking so you can be be a nice guy and not run your gen in the anchorage? If so I applaud your idea and probable practice.

Question:
If I was to get a small gen like a "Honda" how would I connect it to my boat? Just get the proper plug and plug it into the same receptacle as we do for shore power?

 

[N4712]

Very good question Aquabelle and I don't know the answer but think it should'nt be a problem. Harbor Nights are you asking so you can be be a nice guy and not run your gen in the anchorage? If so I applaud your idea and probable practice. Question: If I was to get a small gen like a "Honda" how would I connect it to my boat? Just get the proper plug and plug it into the same receptacle as we do for shore power?

Yeah just get one of these.

 

[Daddyo]

My genset is in the stern as is the pickup for the genset. It has the mushroom pickup and is an Onan 7.5.

What do you all think of a genset running at cruise of say 7-9kts. We would only need this for say christmas lights or maybe baking underway.

We have a twin engine and I was wondering if the prop wash would interfere with the water flow of the genset pickup.

Any suggestions?

Won't your inverter/alts keep up with this?

 

[magicbus]

We have a Mastervolt system (actually 2 as we have 5 distinct battery systems) that takes various charging inputs and manages them.

Dave

 

[N4712]

We always run the genset underway

 

[N4712]

Do you turn your battery charger off when running genset underway? To avoid confusing the engine alternators, which would otherwise be 'seeing' multiple charging sources hitting the batteries?

Yep, always.

 

[Edelweiss]

Do you turn your battery charger off when running genset underway? To avoid confusing the engine alternators, which would otherwise be 'seeing' multiple charging sources hitting the batteries?

No, Xantrex charger with three battery bank circuits. Charger detects the alternator charge and will switch that bank into standby mode. Shut the engines down and the charger puts the battery bank back in charge mode.

 

[gwkiwi]

Do you turn your battery charger off when running genset underway? To avoid confusing the engine alternators, which would otherwise be 'seeing' multiple charging sources hitting the batteries?

Very good question and the answer can vary.

Those with a modern inverter have no problems for the reasons posted by others, however without an active inverter with the gen running and the 110 battery charger breaker on in conjunction with the alternators running and yes you can cause an issue, dont ask me how I know.

 

[ranger58sb]

Won't your inverter/alts keep up with this?

I'm guessing HN has no inverter.

We don't have one either, so for baking underway, genset on.

It happens our genset is on much of the time while underway, anyway, including at planing speeds... mostly to power the aircons... 'cause otherwise the saloon just gets too hot during late Jun/July/Aug/early Sep...

-Chris

 

[Miss Donna]

After having to replace a charger and 4-8d's, I will not run the battery charger with engines on again. However anytime I run more than two hours my genny is on to power the engine room blowers, and of course my surveillance system so I can keep an eye on the Kiwi's.

 

[psneeld]

Not sure what actually causes any problems with alts and chargers on simultaneously...have run many a boat including mine with both going with no ill effects....

 

[Edelweiss]

Not sure what actually causes any problems with alts and chargers on simultaneously...have run many a boat including mine with both going with no ill effects....

I have no idea either. . . .even my automotive charger will shut down if you start the car engine too which it is attached.

My boat is twin engine and the internally regulated Delco alternators are each attached to a battery, no combiner. When you switch the battery switch to "all" and combine the batteries there are no adverse effects?? Both alternators continue running and balance the load between the alternators. If you slow one engine to idle, the other alternator picks up the load.

 

[twistedtree]

I just happened to be reading a paper from Northern Lights about generator installation (I know, I need to get a life). Anyway, they are very clear that you MUST NOT use a scoop thruhull of any kind. The reasoning is that with the generator off and the boat underway, the scoop forces water up the intake line, pushes past the impeller, and fills the water lift muffler (assuming you have one). Once the muffler fills, the water will back up into the engine and trash it. This of course depends on the exact configuration of your installation and exhaust, but it's not a failure scenario that would immediately come to mind.

So, according to them, not only is a mushroom intake OK, its what you MUST use.

 

[Miss Donna]

Sounds like the definitive answer for the original topic.

 

[FF]

>My boat is twin engine and the internally regulated Delco alternators are each attached to a battery, no combiner. When you switch the battery switch to "all" and combine the batteries there are no adverse effects?? Both alternators continue running and balance the load between the alternators. If you slow one engine to idle, the other alternator picks up the load.<

This is normal proper operation for one wire alts.

 

[sunchaser]

Make your life easier- change the electric stove out for a propane one!

Or better yet, induction cooktop with a convection microwave.

 

[Miss Donna]

My convection microwave oven is one of the best additions I've made to the boat.

 

[magicbus]

My convection microwave oven is one of the best additions I've made to the boat.

X2

Dave

 

[rwidman]

..........Make your life easier- change the electric stove out for a propane one!

While I agree that a propane stove is better than an electric one, especially on a boat, "changing out" an electric stove for a propane stove is not that simple unless you already have an ABYC compliant propane system. The requirements for propane on a boat are pretty complex and strict.

 

[psneeld]

While I agree that a propane stove is better than an electric one, especially on a boat, "changing out" an electric stove for a propane stove is not that simple unless you already have an ABYC compliant propane system. The requirements for propane on a boat are pretty complex and strict.

But not necessarily hard...I put a propane stove back on my boat (PO had switched to electric) in a day after I had all the pieces and parts...But some boats are a lot tougher or personal requirements may make the install difficult.

 

[BruceK]

Not sure what actually causes any problems with alts and chargers on simultaneously...have run many a boat including mine with both going with no ill effects....

I have had solar panels, engine alternators, and charger running simultaneously, no problem I know of, but friends fitted an auto cut out for panels when the engine was running.