Has anyone done this conversion on a Onan 4K and what was the cost and where did you find the best price on parts needed.Thanks John

If this is in a motor home why would you do that unless it’s permanently parked somewhere.

I've thought about doing it with my 5500 Onan, just to make sure that it doesn't get gummed up with gas when it sits for long periods. I've not done it, but it looks relatively easy to do and there are kits on Ebay, and other places that make it look pretty easy. OTOH, if you use the generator much propane usage is pretty high.

wildtoad, no it is in a 5er,fj12ryder, yep getting tired of a gummed up carb after sitting longer than two months and yes I do know propane use will be higher and cost a little more.

I've had mine for 8 years and use the generator very, very infrequently, and have had no issues with the carb gumming up. I thought it would be an issue since we are fully connected almost all the time. But it hasn't been a problem. I drain the carb bowl after I'm through using it, and it always starts right up when I start it again months, sometimes many months, later. It usually gets started maybe once or twice a year. I never use any stabilizer, never drain the gas tank, and the same gas has been in there for a good 5 years. Like I said, so far no problems. Now watch, it won't run for sour apples this year. LOL

convert gas generator to propane | Good Sam Community

camperdave
Explorer
Jan 10, 2019
Bill.Satellite wrote:
Your gas generator has a 90-100 gallon tank of fuel to run off of allowing for few concerns about needing to refuel often.

Haven't seen many fivers with a 100 gallon fuel tank! :B
JimK-NY
Explorer II
Jan 10, 2019
Not only is propane expensive and bulky, but it is often hard to find. In my area the refueling stations have closed. There are plenty of exchange places but there are some issues. First the tanks are only filled to 15 instead of 20 pounds. I don't understand why except that this makes more money for the exchanges. Next the exchange tanks are often in bad condition, years and years out of date and do not show re-certification. You will not be able to get one of these tanks refilled.
midnightsadie
Explorer II
Jan 10, 2019
I run a few BOATS .just add sea foam to your tank run gen for a bit ,then forget it, some of my motors sit over a year and take off and run just fine. I do like the fuel shut off valve idea think thats a very good idea.
Bill_Satellite
Explorer II
Jan 10, 2019
I am sorry to be another offering no information about your conversion, but I had a propane powered generator and it was a terrible mistake to have not put in a generator that ran on the same fuel source as the coach. Your gas generator has a 90-100 gallon tank of fuel to run off of allowing for few concerns about needing to refuel often. Should you change to propane you are also going to need to find a location to mount a 100# propane tank as you will burn through propane pretty quickly. On a very hot weekend in Virgina we were dry camping and the generator had to run 24 hours a day and we had to refuel fuel before the weekend was over. That would never have been an issue if I had been using my 100 gallon fuel tank. Propane is also generally more expensive than gas and it derates your genset by about 500 points (5000 would not be rated 4500).
joebedford
Nomad II
Jan 10, 2019
When we bought our new toy hauler, second on the list of must haves after tri-axle was gasoline generator.
romore
Explorer II
Jan 10, 2019
Add Sta-Bil or a similar product to the gas and run the generator long enough to get it to the carb.
MrWizard
Moderator
Jan 10, 2019
no info, because converting a built in gasoline onan

is a Very Rare thing

people usually convert portable generators

or maybe a stick house emg backup generator

BTW we had a Dp with LP onan, it was a liquid feed system
with a vapor/converter at the genny, needs a special LP tank

diy conversion kits for gas to LP use vapor systems and standard bottles,
johntank
Explorer
Jan 09, 2019
Since I have not gotten any info on the conversion I will not be checking in for some time, maybe several days.

Thanks
JaxDad
Explorer III
Jan 09, 2019
If the Onan is in a 5’er it must then have its own fuel tank. It would be pretty easy to dose it up with SeaFoam then compared to a m/h where the fuel supply is the chassis tank.

Seems a bunch easier to just prevent the gumming up in the first place.
Dusty_R
Explorer
Jan 09, 2019
On our '01 Itasca 24' mh I installed a switch on the fuel pump, and when I knew that we were not going to use the generator for a while I would turn the fuel pump off and let the generator run out of gas. That worked fine. Never had a problem with gummed up carb.

Dusty