Attaching a 5KW generator to the main 45 HP boat engine

[mikecambrai]

When you are just running the engine to charge batteries, when you want to increase the load to give the engine a blow out, you cannot do it because you have no other load when you are stationary.
We never asked what this 5kw of power was for anyway!

[Colin A]

In commercial boats they often use clutches to hydraulic pumps. You should be able to adapt one to an alternator. It would require a lot of fabrication. But in theory you could run a short coupling off the front of the engine to a clutch and alternator. You could then bring in the alternator when used for just power production then just return to the normal alternator when motoring.
Marine Applications

[a64pilot]

I don't know about you guys, but in my boat, it wouldn't fit, physically as in no room. It would take considerable modification to make it fit. How many people have a foot or two in front of their engine, or a foot or to on the side? I think it could be done with a PTO transmission, but now you have to add that cost too.
You could make it work of course, but it would be more difficult than installing a stand alone generator, and I believe even more expensive.

Really, when you go about wanting to do these things that from an Engineering perspective aren't all that hard to do, but isn't usually done, ask yourself why first. Often the answer is yes you can, but why would you want to?

I'm going the three legged stool approach myself, I have 750W Solar now, and can add another 500W on the Bimini if needed, but that is about realistically all I can do, I have a Diesel genset and about as large an alternator as I can get to fit and a 3 KW inverter.
I see the logic in adding as much generation to the engine as is practicable so that when the generator is inop you can still drive on, but to use your main engine as the primary electrical generator is I think a mistake.

[Dockhead]

Originally Posted by mikecambrai

When you are just running the engine to charge batteries, when you want to increase the load to give the engine a blow out, you cannot do it because you have no other load when you are stationary.
We never asked what this 5kw of power was for anyway!

Sure you can! Just put the boat in gear.


In fact that's what I do when I use my main engine to charge instead of the generator (rare cases). Let it run for a while at fast idle, then put it in gear and wind it up for while, repeat.

[Terra Nova]

Originally Posted by Colin A

...you could run a short coupling off the front of the engine to a clutch and alternator...

You shouldn't need a clutch when it easy to remove the electrical load.

[svemmanuel43]

Hi I have a 43 foot Robert Mauritius with 80hp ford Lee's I mounted a 6kva 3000rpm altin at or above main engine using twin B section belts and a magnetic clutch off old car air conditioner. Very small pully on alt. The yacht also runs a 6kva Genet so I call the one on the main engine a cruise altinernater. It's a good backup for Genet also when motoring don't need to run Genet to cool beers, as well on those cold passage making nights when there is no wind it's very nice running to fan heaters in the cockpit. Have pully ratio set for 5 knots at 50 hz have hz meter on dash to adjust rpm depending on load

[MikeTC]

I have an A$1100 Kipor 2.6kw generator to back up 800w of solar. Magic! Can't believe anyone would spend A11k on a genset. If your thinking of the hassel factor of getting it out of the sail locker....think of it as saving on gym fees. 14min running and we have a hot shower for 4. I'm thinking of a 12v element 100w to heat the water each day on a timer but need to add some more smarts ie cloudy days.

[GordMay]

Greetings and welcome aboard the CF, Andy, & svemmanuel, & Mike.

[Greggegner]

I would like to put one of these electric motors/generators inline behind the transmission. Charges with a freewheeling or underpowered prop and is a second power plant.


http://electricyachtsocal.com/product/h-drive-sail-8-0/


Greg S/V Sweet Dreams
Pearson P385 out of Racine Wisconsin

[Colin A]

Originally Posted by Terra Nova

You shouldn't need a clutch when it easy to remove the electrical load.

Thats funny I didn't even think of that at first, but of course your right.

[Lucky]

Originally Posted by Dockhead

Generating 4kW of power takes about 8hp of mechanical power, so 18% of rated maximum -- you sure that's harmful? I don't think I'm using more than that at economical cruise with my engine. In fact judging by fuel consumption I'm only using about 12-13 hp or 12% - 13%. I would think a 4kW generator would be an ok load even for my 100hp Yahmar.

Of course following Yanmar's instructions you have to open it up periodically, but I do that economical cruising too.

The generator specialists I have delt with claims that a diesel engine love to be run on approx 80% of full load! That prevents carbon build up inside the engine and gmlazing of the the cylinder bores.

My two cents passed on from the pros.

Happy lead free sailing from Lucky

[Cadence]

Originally Posted by Colin A

Thats funny I didn't even think of that at first, but of course your right.

You may not need a clutch but it may save some wear and tear on the belt and genny bearings?

[a64pilot]

Originally Posted by Cadence

You may not need a clutch but it may save some wear and tear on the belt and genny bearings?

You would have to have one big clutch, that is why I think to make the most sense a transmission with with a dedicated PTO would be the way to go, ideal I think would be DC so RPM is irrelevant, and an inverter to make AC.

But if you wanted to belt drive, I would think a toothed drive belt like used on Motorcycles would be good, many years ago Kawasaki had a belt drive on a twin cylinder 450 machine, real similar to belt driven cams on many cars.


Sent from my iPad Pro using Cruisers Sailing Forum

[Cadence]

Originally Posted by a64pilot

You would have to have one big clutch, that is why I think to make the most sense a transmission with with a dedicated PTO would be the way to go, ideal I think would be DC so RPM is irrelevant, and an inverter to make AC.

But if you wanted to belt drive, I would think a toothed drive belt like used on Motorcycles would be good, many years ago Kawasaki had a belt drive on a twin cylinder 450 machine, real similar to belt driven cams on many cars.


Sent from my iPad Pro using Cruisers Sailing Forum

I agree on the Gilmore belt. I'm not sure I agree with cobbling something together. I may be wrong it wouldn't be the first time.

[Sailor Doug]

Most Harley's use a tooth belt but I still would worry engine would not take side load


Sent from my iPad using Cruisers Sailing Forum