Convert Onan From LPG To Gasoline

[rlbarkleyii]

I want to either convert my 02' Onan 6500K LPG to gasoline or exchange it for a gas model. Can these gennys be converted to gasoline reasonably?

I want to be able to run the genny from extended remote tank for long periods and refuel it from jerry can without moving unit.  The difficulty of finding bulk  propane 24/7 on the road and while boondocking is the reason for the change.

Appreciate any suggestions

[hermanmullins]

RL,

You might consider getting a 100 lb propane tank or even several 25 lb tanks and an automatic switch over valve like they have on trailers. Either one should last longer then a Jerry Can of gas.

Herman. 

[manholt]

Figured you had already thought about Herman's idea...hard to carry all that around with you, until you get to the outback!   Yes, you can convert, but I would call Cummins since they own Onan.  Don't know cost!

[kaypsmith]

100# tank good idea, don't depend on the automatic change over valves for extra storage. The auto change valve has a built in regulator, and the generator has an onboard regulator, the two in this condition causes the auto change over to take place at the 50% level, this causes both tanks from emptying below 50% level. I fought that problem for nearly a year before discovering what was happening. I don't know about the Onan setup, but many generators have a changeover built in to allow use of either gasoline or LP gas, a call to Cummings/Onan should be able to answer the OP.

[jerrycarp]

My onan 6300 lp gen uses liquid for gen vapor for all else. I believe 100# and smaller tanks are just vapor?

 

Jerry

[desertdeals69]

I have done the conversion.  It requires a fuel pump and a carb.  Not hard to do.  I have even changed a gas model to a propane.  Those model of Onan propane use liquid so if you need to run them on a portable tank you need to use a 5 gal barbecue tank turned upside down.  I don't know it a larger tank is possible to turn upside down or not.

[wolfe10]

While many of the Onan 6500/6300 LP generators WERE designed to run on liquid LP, they run very well on HIGH PRESSURE VAPOR.  Yes, that means BEFORE any regulator on the tank.

This also materially extends the life of the on-generator regulator, as the long-hydrocarbon contaminants in the liquid are not present in the vapor.

This was done with input from a engineer at Marshall Gas and worked fine  on our 1993 Foretravel with liquid LP Onan generator. After conversion, it  ran for many hundreds of trouble-free hours (and as far as I know continues to run well today-- many years later) after the "conversion" and overhaul of the on-generator regulator. When overhauled, the regulator was clogged with several tablespoons of what looked like a light-viscosity grease (contaminants collected over the years of operating on liquid LP). 

Yes, if the tank is too small to dissipate the "cold" resulting from the expansion of the gas, this could create a problem in very low ambient temperatures.  But, it that occurs, just turn the tank upside down.

[kaypsmith]

My LP Honda generator will work on liquid also, but the use of a changeover valve was the culprit on trying to changeover from tank to tank automatically.

[rlbarkleyii]

WHOA EVERYONE!  Maybe I didn't make myself clear.   I currently have a ONAN  6.5K HGJAB-902A Marquiis III, (600hrs) high pressure, LPG,  and I would like to convert it to unleaded gasoline, not propane. Is this possible has anyone else done it?  If so what is involved cost wise parts and labor? What parts have to be replaced?  What effect will in have on the life of generator?

 

[wildebill308]

I think the only problem is running a fuel line, with fuel pump and filter and installing a carburetor. I wonder if you could find a parts breakdown on Cummins/Onan that should give you all the parts. It looks pretty straightforward. I don't think longevity would be affected enough to worry about. 

Bill

 

[desertdeals69]

4 hours ago, rlbarkleyii said:

WHOA EVERYONE!  Maybe I didn't make myself clear.   I currently have a ONAN  6.5K HGJAB-902A Marquiis III, (600hrs) high pressure, LPG,  and I would like to convert it to unleaded gasoline, not propane. Is this possible has anyone else done it?  If so what is involved cost wise parts and labor? What parts have to be replaced?  What effect will in have on the life of generator?

 

Read my post above.

[manholt]

And mine above that.  I did not know about cost until DD69 said fuel pump, fuel line and carb.