generator hours

[Kurt]

I am looking into buying a little older but bigger boat with generator. The question I have is: what is normal or what is considered normal hours on the generator for say a 2002-2003 boat with a 5k generator? If so any pros and cons to different brands that you have experienced would help, thanks. :huh:

 

[Sea Gull]

It's hard to pin down generator use. On my boat there is lots of AC stuff so my genset runs all the time that we are away from the dock. The only time it is shut down is if we are anchored and swimming or otherwise hanging around the swim platform, or when we are sleeping on the hook. So, in my case the genset has about double the hours of the main engines.

On smaller boats that don't rely so heavily on AC power it is more common not to run the generator at the same time as the engines. (The exception would be those who need to run cockpit air conditioning while underway.) On these boats the genset gets used at anchor and maybe overnight in some cases. The hours should be significantly less than the hours on the mains.

Of course all of this depends greatly on how and where the boat was used, but generators can last a long, long time IF properly maintained. Remember that they are running at a steady RPM with a predictable load, so they don't see the same stress as the mains.

 

[fc3]

It doesn't matter, as Sea Gull said. As long as the engine was maintained, it should be fine. Westerbeke seems to be the better of the gasoline generators. I've had mine apart, due to a stupid winterizing mistake. It's pretty well built and easily serviced. Parts are available, but the engine is a Mitsubishi not widely used in the US, some parts can take a while to arrive if Westerbeke is out of stock.

Best regards,
Frank

 

[Bottom Line]

Kurt...I have seen hours on generators all over the map....and some if it probably has a little to do with the size of the boat. I only run my generator when we (mainly the kids) want to go into the cabin and want to have the air conditioning on and watch a movie. I only have about 60 hours on mine generator...and it is a Kohler. Sevaral of the boats on my dock will start the generator before they leave the dock...so it runs constantly when they are not at the dock. As a comparison...we have a 2003 420DA for sale on our dock....and it has about 1800 hours on the generator. Good luck with the hunt... what are you looking for?

 

[skolbe]

I have the new low CO model Kohler. So, far it seems to be a great setup. It seems as if most generators are not used enough and therefore their useful life is greatly reduced. If used regularly and maintained properly you can get 1000's of hours out of them. But most are used a handful of hours a season. I know my friend bought a 10 year old boat with a Westerbeke and at 80 hours it had to be completely rebuilt. Then you have people that have 5 year old generators with close to 2000 hours on them and no issues. Use and maintenance are key.

 

[fwebster]

Depending upon how big "bigger" is, some boats have auxilary systems, like power steering, driven by the generator motor. In those cases, you will have at least as many hours on the generator as the main engines. In acutal practice, most pleasure boat owners run A/C or heat, refrigerators, freezers and ice makers the whole time they are on their boat. Then, some of us prefer quiet to some of the creature comforts.

Examples:
A friends Viking convertible......1200 hou®s on the mains; 6800 on the generator
My 450.....1000 hours on the mains 1290 on the generator
A friend's 320DA.......95 hours on the mains; 400 on the generator
The 460DA next to me.......375 hours on the mains; 150 on the generator

They are all over the map, and all of those generators are in like new condition and get regular maintenance.

So I don't think there is a single answer for every situation. I will agree with FC3 and the others that regular and proper service is more important than run time.

 

[fc3]

One more data point. Goes to quality. Generators run for long periods of time at stable RPM, pretty stable load, and pretty stable temperatures. This allows the manufacturer to set the engines up more precisely. They pay more careful attention to details like clearances. For example, Toro uses the same Mitsubishi engine for some of their stuff that Westerbeke uses. Westerbeke lists a half dozen or so journal bearings based on inside and outside diameter. You must have a good micrometer to precisely measure the crank and block and get the right bearing. Toro lists one bearing. Closer attention to tolerances means longer life, if the engine is properly maintained.

Best regards,
Frank

 

[Kurt]

Excellent answers here really showing the experience of the forum boaters. I agree with regular and proper maintainence of anything so I guess no difference here. Now if I could only convince my wife of this. I never really put it into perspective regarding constant RPM and loads, that helps a bunch to understand why it would last a long time. I am looking into several 260's 2004-2006 and trading my 2007 240 in. Thanks all

 

[skolbe]

You also want to keep your generator in the 30% to 70% load range while it is running. You have to guess on the appropriate load. For my boat I usually just have everything on (A/C, Charger, Hot Water...). Then before you shut down take the load off and let it run without a load for a minute or two. You also should try to run the generator under load at least an hour every other week, when not winterized.

 

[Hampton]

I have about 290 on my mains and about 800 on my genny. We use them completely differently. If we drive 70 miles to Destin or Apalachicola, we stay at a marina and don't use the genny. If we drive 3 miles to Shell Island, we'll use the genny about 8 - 10 hours per day for 1, 2, or 3 Days.

We do about 4 longer trips/year and 20 shorter ones, so, the genny adds up. Even on longer trips, the boat engines only run for about 3 hours each way compared to 20 hours on the genny on short trips.

 

[rondds]

interestingly, there has been a rash of folks at our marina with genny problems that have gone largely undiagnosed b/c they just dont use them. the attitude seems to be "who cares if it doesnt work, i really dont use it anyway, right? WRONG. when i bought this boat in 2004 the generator had about 185 hours on it. and for 4 seasons after i RARELY used it. i'll literally start it on the hook every now and then to warm up left over pizza in the toaster oven for my daughter. but every fall i'd change the barely used oil, run pink stuff through the system, pull the plugs, spray fogging oil into the cylinders, crank it and put the plugs back.

that was until this season. these are small japanese engines, and like all engines, they like to be run. so i started running mine more this year. underway, on the hook, even at the dock if it's been a while since it had been run. i had done the math in an earlier post, but on a quicksilver generator (which is a 989cc 4 cylinder nissan engine) with 1000 hours, the automotive equivalent would be around 30,000 miles of use assuming an average speed of 30mph. in a car, rpm fluctuates and revs tend to be much higher than with a governed generator. BUT in a car, the environment is not nearly as hostile (poorly ventilated, constantly damp, salty). so it all evens out. i think we'd all agree that 30,000 miles of light use on a nissan or mitsubishi engine is not all that much, assuming maintainence was carried out to spec.