Small built-in gensets, propane vs. diesel

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Back2PA

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I have a neighbor soon to be buying a newer, used small diesel powered motorhome that came with either a propane or diesel 3KW genset (both are Cummins/Onan). I would love to hear some feedback from owners of each to pass along. Considerations such as noise both inside and out, fuel usage, reliability, etc. Thanks
 
Roy M said:
What make? How many hours? Has it been maintained? Does it run/produce power?


I?m asking for feedback from owners of these gensets. In this case both the propane and diesel version are Cummins/Onan
 
Any given unit will have one or the other, it is not likely a choice unless ordering new, and on most diesel powered motor homes it will be diesel. The exception might be the small Sprinter based motor homes, 30 amp models (3600 watts), they are often equipped with propane fired units. Propane units are known to be propane hungry as there is not as much energy in a gallon of propane as there is in a gallon of diesel oil. One is as 'noisy' as the other but diesel units are heavier (weight wise) than propane (which, in reality, are simply a modified gasoline generator). Both are reliable when maintained properly.
 
Yeah, the Sprinter-based B & C coaches typically have an LP genset as standard and diesel as the upgrade option. The diesel genset runs from the main fuel tank vs the rather small LP tanks those rigs carry.  An LP genset consumes fuel at a higher rate because LP has less energy/gallon than diesel. Thus the LP genset consumes more gallons of fuel per hour and gets it from a smaller tank, so more limited in its use.

Knowledgeable buyers who expect to use the genset regularly prefer the diesel genset but most buyers don't want to pay the higher cost of the diesel, so dealers tend to order LP gensets for their stock.  The manufacturers, of course, like to advertise the price based on the lower cost LP genset.
 
All, thx. This pretty much mirrors what I told him already. Whether he can find one with a diesel is the question.
 
I have had gas and propane Onans, the only diesel I have heard in a small (Winnebago VIA) motorhome was quite loud, one of the reasons we stopped considering the coach.
 
OLDRACER said:
the only diesel I have heard in a small (Winnebago VIA) motorhome was quite loud


I was curious about that. The 7KW Onan Quiet Diesels are indeed quiet (I wish I had one), but wondered about the little ones that are space constrained for install. Are they air cooled?
 
My diesel pusher has a gasoline generator. Before buying this mh, I had never heard of a gas genny on a diesel pusher. I have a separate tank and gauge, as well as filling spout. I can only guess as to why the original owner got it that way. One reason I can think of is that some people get sick at the smell of diesel fumes. I can see driving a diesel not bothering you, but camped with the fumes from a diesel genny might. I personally wish it had the diesel, but when you get a deal, you get what it came with. I wouldnt want a propane one. Too much fuel used out of my already too small propane tank. When camping in cool weather, the propane gets used up fast enough by the furnace.
 
THough I have used both Propane and Diesel generators I do not own either.

Propane sucks a LOT of gas and thus you may find run time limted on many motor homes  But they tend to be less noisy than a Gasoline or Diesel generator

Diesels suck from the main engine tank so run times of 50 to 100 hours (Full tank) without re-fueling.. Quite common.
 
Would that be 50 to100 hours out of a probably 70 gallon diesel tank (assuming a  reserve below pickup)?

What price AC??? Wow.
 
My diesel generator (6.5KW cummins) says .5 gal per hour at no load and 1 gal per hour at full load.  I never actually checked it.  Hard to tell with a common tank.
 
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