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VeggieBullet · 08-16-2012, 05:02 PM

Is anyone familiar with the Onan 4.0RV Genset?
It seems to be from the 80's anyone familiar with the specs, how does it run, fuel efficiency?
We can get it for a real, a real good deal..so please help.
Here is the info in the plate.
Onan 4.0 RV Genset
Model BFA-IR / 15004C
Serial K803 533630

Regards
Gus

PeterH-350LE · 08-16-2012, 09:17 PM

Quote:

Originally Posted by VeggieBullet

Is anyone familiar with the Onan 4.0RV Genset?
It seems to be from the 80's anyone familiar with the specs, how does it run, fuel efficiency?
We can get it for a real, a real good deal..so please help.
Here is the info in the plate.
Onan 4.0 RV Genset
Model BFA-IR / 15004C
Serial K803 533630

Regards
Gus

If it runs and can handle the load of the roof A/C, go for it. They use less than 1 gal per hour and are very dependable and fairly quiet, if they run.
The biggest problems with the old gensets is the carburetor. They get worn out and suck air at the linkage, which renders them useless. Fire it up and put it under load before you buy it

ROBERTSUNRUS · 08-16-2012, 10:37 PM

Hi, I would want to see the hour meter.

VeggieBullet · 08-17-2012, 06:30 AM

thanks guys,
Less than 300 hours according to the meter.

Now wondering if the 4K stands for running or starting power?

Skater · 08-17-2012, 06:58 AM

I'd worry more about an Onan generator with low hours than too many. 300 doesn't sound like a lot to me given the age (if it is from the 80s). Low hours means it hasn't been exercised regularly, and one thing I learned with my Onan 2.8 is that they do not like to sit unused. They get hard to start and seem to be more prone to stalling.

VeggieBullet · 08-17-2012, 07:22 AM

any idea about a full maintenance/service costs?
BTW how quite are they? again, we can't find anywhere online about if the 4KW is for running or max loads

PeterH-350LE · 08-17-2012, 08:12 AM

10 years ago , I called Onan about full maintenance options. They told me that they no longer support those Gensets and that many parts are no longer available (as in carburetor). Other low level maintenace parts are still available (plugs, points, condenser, oil filter).

4kw max, if its in top shape

VeggieBullet · 08-17-2012, 09:03 AM

Hi Pete.
thanks for the PM!
10 years ago they couldn't rebuild it? wow... it looks like I found another vintage item..

so 4K max will give us a 3K running?

VeggieBullet · 08-17-2012, 11:25 AM

Just got this reply from Onan customer service:
Per your s/n this unit was mfg in 1980. The model # is 4.0 BFA-1R / 16004 C. I have attached a copy of the operators manual 965-0122 for your use. Service and parts manauls can be order from our distriubtor or at our online RV strore at http://www.cumminsonanstore.com/
The 4 kw or 4000 watts is the max running / starting watts

Also called OnanCummins in Tampa and the service guy told me that a full service and including replacing the carburetor is around $600. Also stated that all parts for rebuilt it are available.
The part that it wasn't clear is that the fuel efficiency is about 0.20 to 0.30 gallons per hour, based on those numbers we have a generator that uses only 6 gallons a day? mmmm to good to be true

Is anyone out there with an old Onan still kicking?

**DKB_SATX** · 08-17-2012, 11:41 AM

That fuel burn rating is most likely at a fraction of full load, and as such is believable. My 3kw Yamaha is rated for 19 hrs at 1/4 load, and based on the tank size that's a burn of 0.18 gallons/hr.

I don't think you'll get that fuel burn while you're running the AC, charging dead batteries and watching TV all at the same time, but in Florida you'll probably be willing to feed it the fuel it needs to keep the AC running.

GetOutDoors · 08-17-2012, 11:44 AM

... that unit is made to last up to 5,000 -6,000 hours before needing a rebuild.

Does it have a gas or propane carburetor on it?

The issues priorly expressed about it being hard to start can be avoided by using a propane carb. Gas will mess up the carb if left without use.

PeterH-350LE · 08-17-2012, 11:53 AM

Good news for you!
This is the unit (1979 4.0 BFA) I inquired about in 2001 and was told that it was no longer supported. Maybe there was a huge demand in the last 10 years that prompted them to provide parts again.

VeggieBullet · 08-20-2012, 09:33 AM

Hello guys, sorry for the delay on getting back online..

DKB SAT
That fuel burn rating is most likely at a fraction of full load, and as such is believable. My 3kw Yamaha is rated for 19 hrs at 1/4 load, and based on the tank size that's a burn of 0.18 gallons/hr.
I don't think you'll get that fuel burn while you're running the AC, charging dead batteries and watching TV all at the same time, but in Florida you'll probably be willing to feed it the fuel it needs to keep the AC running.
I’m pretty sure that the burn ratio is based probably with no load, how will they estimate that I’m not sure since this particular model unlike a regular generator does not have a fuel tank. Most of the time has a fuel line connected to the gas tank of the MH and with an independent fuel line pick up that will only go to ¼ of the tank so in case you didn’t have enough fuel when you stopped to sleep that will avoid the generator to burn everything you have and when you wake up you can’t go anywhere LOL
We are planning on adding a 20 gallons fuel tank for the Gen with the remote starter, now wondering about monitoring the fuel level…

Get out doors
... that unit is made to last up to 5,000 -6,000 hours before needing a rebuild.

Does it have a gas or propane carburetor on it?

The issues priorly expressed about it being hard to start can be avoided by using a propane carb. Gas will mess up the carb if left without use.
5 to 6K hours!??? Wow… I’m more than happy to read that! The current carburetor is Gas and didn’t know about converting to lp, if that is done how will that affect the fuel efficiency on the Gen? all I heard from LP gens owners is bad things about how much they burn and that they wished it was a gas one!

PeterH – 87MH
Good news for you!
This is the unit (1979 4.0 BFA) I inquired about in 2001 and was told that it was no longer supported. Maybe there was a huge demand in the last 10 years that prompted them to provide parts again.
Well I don’t know the reason but is great, and even if we need to take it to onan to do the $600 full service with a new carburetor it doesn’t sound bad considering the life of it!
That is a cool pic! That is exactly we we have in mind to built for the generator, wondering if you have a pic of the compartment door once is closed. Another question: is that MH Gas or Diesel? If the MH is diesel I’m assuming an independent gas tank for the gen?
Thanks again guys!