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Why Do Marine Generators Suck So Much?

PostPosted: Tue Sep 26, 2017 11:28 am
by EpicWakeJump
And I don't mean suck gas or water. I mean many have horrible reliability that can't match Hondas or Yamahas.

What's the deal with that? I'd kill to have one of my Hondas installed on my boat!

Why can't our American made generators compete with the Japanese? Ugh...

Re: Why Do Marine Generators Suck So Much?

PostPosted: Tue Sep 26, 2017 11:43 am
by gofast24
My thoughts =
Our as far as i know none of our domestic gen set manufactures make a economical 2 or 3 cyl. water cooled engine, the competition (Honda and Kawasaki, Yanmar) all make great (as the POTUS would say) high efficiency water cooled "motor cycle" engines. Its just natural for these guys to design a water cooled gen set using the technology from the water cooled base motorcycle engines, not much to change/modify). Our 15 year old Westerbeke 7.0 kW gen set (1800 RPM, a 3 cylinder Mitsubishi counter balanced automotive derivative water cooled engine ) runs like a sewing machine! Checking Westerbekes current marine gen set offerings almost everything below 6/8 kW is a 3600 RPM water cooled foreign manufactured motor cycle derivative! I believe when you get above 8/10 kW you will most likely see a cummins / JD/ etc. 4 cylinder diesel but that means you would most likely you would have to have a diesel propulsion engine? Dont think many 46+ foot vessels have gas engines anymore? May be wrong here though.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Tue Sep 26, 2017 12:02 pm
by EpicWakeJump
How many folks REALLY trust their generators?

I trust my VP 300 WAY more. It's like the most common engine found on earth likely.

But I've never trusted my generator from the start and it's proving me right.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Tue Sep 26, 2017 1:36 pm
by Batchski
I could have written this same post myself, as I have often wanted to vent about the generators. My 2005 Kohler was reasonably reliable, but my 2014 Kohler is a nightmare. Even when serviced by Kohler techs, the thing throws quirky codes and shuts itself down, only to work fine for hours once the code is reset and it's started again. Of course it fails again sooner than later, just when I have guests on board and I need to start the grill. Off I go to the engine room, to reset the code and get it to start again. Most times it's a different code than before, with my favorite being "engine fault." I've repeated this process now multiple times, and of course had it serviced my the local certified techs, who only tell me what I already know: it's a sensitive dang unit that I will just have to tolerate. Honda makes great outboards, and I wish they would make marine generators and put these others out of business.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Tue Sep 26, 2017 2:33 pm
by TechRider
My generator has had no issues. It's only one season old.

Starts right up, runs for hours providing flawless power.

I hope I don't see any issues. It was expensive!

Re: Why Do Marine Generators Suck So Much?

PostPosted: Tue Sep 26, 2017 7:25 pm
by Chris_in_Texas
I guess that is why the marine genny field got a bunch smaller in the small gas realm. Kohler no longer makes gas units for the marine side. I assume that is why Regal started using Westerbeke units now for all the small gas units. :shock: I am not sure who else is left in the segment.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Wed Sep 27, 2017 9:03 am
by timp4411
Hi Chris.

I had no idea that Kohler got out of the Marine Generator business.

Thanks for that tid-bit.

Regards, Tim

Re: Why Do Marine Generators Suck So Much?

PostPosted: Wed Sep 27, 2017 9:46 am
by kpic24
I could go on for hours, Westerbeke is driving me nuts. runs for 30mins work on it, runs for 2 hours. Think I have it fixed, then go out runs for an hour,ugggggggggggg.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Wed Sep 27, 2017 10:26 am
by TechRider
I am hoping your experiences are not the norm :) They charge a lot for these units and they should work when you need them. So far so good with mine.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Wed Sep 27, 2017 10:31 am
by gofast24
kpic24 wrote:I could go on for hours, Westerbeke is driving me nuts. runs for 30mins work on it, runs for 2 hours. Think I have it fixed, then go out runs for an hour,ugggggggggggg.

Back to my many times stated old philosophy, nothing like a carbureted (or fuel injected) , distributor ignition system, old fashioned 2/3/4 cylinder automotive derivative gasoline engine powered gen set, especially a 1800 RPM (4 pole gen set) unit. I believe our Westerbeke 3 cyl. 1800 RPM,internally counter balanced set has been delegated to the museums as a thing of the past? Our 2001 set starts, runs, holds frequency and voltage, and is like a sewing machine even without sound covers! When running it on the hook over night we almost dont even notice it is running (other than the exhaust discharge noise) , only problem is that when it needs parts they are out of this world expensive (i.e. , a single barrel carb $1100!).

Re: Why Do Marine Generators Suck So Much?

PostPosted: Wed Sep 27, 2017 7:22 pm
by Kikaboo
I have a 2015 Kohler 5K gen and no issues aside from needing to replace the impeller 2 times each season. It seems at best I only get 10-20 hours out of an impeller. Why the heck would that be?

Re: Why Do Marine Generators Suck So Much?

PostPosted: Wed Sep 27, 2017 7:53 pm
by Chris_in_Texas
My assumption on the impeller is that its a different rubber compound than a traditional impeller in the engines and not near as many vanes, therefore bending much more and causing higher stress. Just a guess. They will eat impellers for sure.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Thu Sep 28, 2017 10:57 am
by gofast24
Chris_in_Texas wrote:My assumption on the impeller is that its a different rubber compound than a traditional impeller in the engines and not near as many vanes, therefore bending much more and causing higher stress. Just a guess. They will eat impellers for sure.

Interesting info, in our case the impeller is still the same as when we purchased the vessel 3.5 years ago, about 200 hours on it since then. Got to agree with Chris that the less number of blades require greater deflection to pump the same volume of sea water so they fail much sooner. The bigest problem with cheep rubber impellers is that when they decide to fail they can push a bunch of rubber fragments into the sea water side of heat exchanger, that becomes a big problem to get the chunks of rubber out after a failure! Just my thoughts.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Thu Sep 28, 2017 6:30 pm
by rlynch03
I have always believed the largest issue with Boat Generators is the lack of use.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Fri Sep 29, 2017 2:09 am
by EpicWakeJump
rlynch03 wrote:I have always believed the largest issue with Boat Generators is the lack of use.


How come my Honda can sit for months (or even as much as a year!) with out use and fire right up?

Re: Why Do Marine Generators Suck So Much?

PostPosted: Fri Sep 29, 2017 6:32 am
by cbsmith
EpicWakeJump wrote:
rlynch03 wrote:I have always believed the largest issue with Boat Generators is the lack of use.


How come my Honda can sit for months (or even as much as a year!) with out use and fire right up?


I think there are a couple things here. The sitting doesn't help any genny, but out it in an area with moisture and it is even worse. The other thing is even though the marine gen sets aren't cheap if you took an equivalent size Honda gen set and made it water cooled, ignition protected, designed for the rough ride of a boat, it would end up costing way more than the current marine ones.

In another post you mentioned just removing the existing gen set and putting s Honda in its place. Unfortunately it isn't as easy as that as it would not be safe to run in the bilge for a few reasons, spark ignition sources and co2 being the main ones.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Fri Sep 29, 2017 11:42 am
by gofast24
cbsmith wrote:
EpicWakeJump wrote:
rlynch03 wrote:I have always believed the largest issue with Boat Generators is the lack of use.


How come my Honda can sit for months (or even as much as a year!) with out use and fire right up?


I think there are a couple things here. The sitting doesn't help any genny, but out it in an area with moisture and it is even worse. The other thing is even though the marine gen sets aren't cheap if you took an equivalent size Honda gen set and made it water cooled, ignition protected, designed for the rough ride of a boat, it would end up costing way more than the current marine ones.

In another post you mentioned just removing the existing gen set and putting s Honda in its place. Unfortunately it isn't as easy as that as it would not be safe to run in the bilge for a few reasons, spark ignition sources and co2 being the main ones.

Agree, as well as installing a air cooled non ignition protected, non USCG approved, not insurance company approved, etc. set. We have in rare cases used my middle sons 2kW Honda invertor gen set while on the hook but set it on the fore deck and back fed the output into the shore power inlet plug on the vessel. Just a experiment but the little 2 kW set would not start or run the AC units, just everything else, especially the house battery charger. The gen set ran all night, barely heard it running and no vibration thru the hull, just a experiment in case the ridiculous expensive Westerbeke failed?

Re: Why Do Marine Generators Suck So Much?

PostPosted: Fri Sep 29, 2017 11:47 am
by cbsmith
If you don't want to run AC those 2000w Honda inverter units are a great generator. Almost silent and small enough to carry around. You need to run them on an outside deck or swim platform but other than that they are good. Once you get up into the 3000w + needed to run AC units they aren't nearly as portable and harder to move around and find space on a deck to put them.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Fri Sep 29, 2017 3:40 pm
by lg260ss
cbsmith wrote:If you don't want to run AC those 2000w Honda inverter units are a great generator. Almost silent and small enough to carry around. You need to run them on an outside deck or swim platform but other than that they are good. Once you get up into the 3000w + needed to run AC units they aren't nearly as portable and harder to move around and find space on a deck to put them.


I have a Yamaha 2400w and it starts and runs my AC with no problem. It isn't much bigger than the Honda 2000 and weighs 75lbs or so. It is also super quiet, even when running the AC.

Re: Why Do Marine Generators Suck So Much?

PostPosted: Fri Sep 29, 2017 6:36 pm
by Mhook1
There are two 3000 Honda's with some big differences. Th one I bought is only 78 Lbs ("Handi model") verses the electric start model which is 134 lbs. Big difference when carrying. It runs everything on my boat. Of course not all at once. I have had the air, battery charger and coffee maker all at once with no problems. It's a manual start but starts 1st pull with little effort, worth the trade off for the lighter weight.