Next Generation Power diesel generators

[pete33458]

Hi all: a bit hard to track down any useful information on these. Is anyone familiar with them and could offer an opinion about quality and performance? Especially the 5.5kw, although any opinions would be welcomed. thanks, Pete

[witzgall]

PM Tom from Skinny Dippin'. They have one on their boat.

Chris

[skipmac]

Forum member btrayfors has a Nextgen. As I recall he is generally happy with the Nextgen and the overall quality but has experienced one somewhat esoteric problem. He has an inverter on his boat that has a boost feature (automatically kicks in to add additional AC power if another AC source like a generator or shore power doesn't have enough power to handle a surge like a compressor startup load).

The inverter boost feature doesn't like the power output from the Nextgen and the boost feature doesn't work when trying to start some appliances. He has to put a resistive load on the generator which seems to clean up the waveform and makes the inverter happy and makes the boost work.

Not sure if the newer units have the same problem but seems like something you are unlikely to encounter.

[colemj]

We also have a NextGen (5.5kw). I don't know why you can't find much info - they seem pretty popular, particularly in Florida (where they are made).

It works well. Like everything, it is a compromise. They are small and lightweight, but do run at 2800rpm. While that is better than 3600rpm that most small ones run at, it is noisier than other's 1800rpm units. It does have a "dirty" waveform under non-resistive loads. This is a result of the 2-pole generator head and regulation system. Putting on a resistive load cleans it up considerably.

The engine itself just runs and runs - it is a standard Kubota small tractor/generator engine widely used throughout the world. The genset itself is simply a marinized version of a standard Kubota industrial genset. It is easy to get inexpensive parts for it, although NextGen is pretty reasonable on spare parts prices.

The Markon generator head is fairly light-duty and can be considered a throw-away item after so many hours/years. They are only ~$700 to replace, so not too bad.

The SS exhaust elbow corrodes quickly. Have one made instead of buying NextGen's - it will last forever instead of a year or two.

Inside the NextGen sound shield, the unit is extremely quiet and smooth. If you do not have the sound shield, you will need a soundproof locker/room for it.

Mark

[Cotemar]

colemj,

Did you have a drawing for a better NextGen 5.5 exhaust elbow or did you just give the factory one to a SS welder and ask them to make it beefer?

NEXT-GEN - Marine Power Units

[djmarchand]

I have the 3.5 KW unit based on the single cylinder Kubota, but I can't add much to what Mark said above. It is a compromise for weight and space and it is noisy from the transom exhaust but not inside the boat. The sound shield does a good job.

Looking at the OEM exhaust elbow above I see that the exhaust goes downward from the exhaust port. In some installations, maybe most, this won't allow enough freeboard above the water line for safe operation without sea water backing up into the exhaust port.

If I were building a replacement I would ask the fabricator to make a dry riser section that would go upward as high as you can inside the sound shield and maybe higher if you don't use the sound shield. Then two elbows to point downward where the raw water enters.

The newer designed injection elbow on the 3.5KW unit is made this way to avoid these problems that were experienced on the older design which I suspect looks like the picture above.

Take a look at the drawing below for best practices in marine exhaust system design, courtesy of Tony Athens, Seaboard Marine and modified to show alternate approaches- flapper, check valve, equalization line. The two important elements are the 12" spillover height and the spillover point being higher than the muffler exhaust. Both of these elements make an inherently safe exhaust system.

David

[colemj]

I gave the existing one to a SS fabricator and asked it be made from schedule 80 and polished. The OEM one is sheet metal thin, unpolished and the welds corrode quickly.

Mark