Forum Discussion

polar76's avatar
polar76
Explorer
Jul 21, 2015

Converting LP to high pressure vapor for generator?

OK,
My generator does't seem to be getting fuel from the LP tank (AGAIN)
So I have looked up the instructions that Mr. Wolfe had posted long ago about converting an Onan 6500 watt LP genny from liquid to high pressure vapor.

"To convert from liquid to high pressure vapor:

Close the liquid port and start the generator to burn off all fuel in the line. Remove the line to the generator from the liquid port and permanently cap off the liquid port. Then install a "T" between the tank and the house propane regulator-- I add a ball valve so I can shut off all fuel to the generator if I so choose. Then move the hose supplying the generator from liquid port to the new high pressure vapor port.

You are finished.

If you are not qualified to work on LP gas systems, a local dealer can do it at relatively low cost."

Just to make sure that I understand,
Do you leave the regulator that is mounted on the generator in place?

I will probably have to replace or clean the regulator also.

Thanks in advance for your responses...
Class A

6 Replies

  • polar76's avatar
    polar76
    Explorer
    Jul 21, 2015
    Thanks Kayteg1
    I will double check for that filter , but I don't recall having one.
    and as for the size of the tank, it's pretty big as I recall it holds 41 gallons, takes up a whole bay.
  • Kayteg1's avatar
    Kayteg1
    Explorer II
    Jul 21, 2015
    The only thing you are risking by switching to vapor is that with small tank and cold weather the tank can "freeze" but that doesn't happen very often.
    I would check the system for in-line filter as with liquid it is usually installed before regulator and is the first thing to clog.
  • polar76's avatar
    polar76
    Explorer
    Jul 21, 2015
    Thanks guys,
    I thought it probably should be left in.

    Brett I have a new regulator ordered supposed to be at South Plains Cummins in OKC in the morning...
  • wolfe10's avatar
    wolfe10
    Explorer
    Jul 21, 2015
    Yes, the on-generator regulator IS important-- you are just feeding it with high pressure vapor (can be over 100 PSI) instead of high pressure (same pressure) liquid. No long hydrocarbon chain contaminants in the vapor-- could be plenty in the liquid.

    And, this will NOT clean out a clogged regulator, it will just prevent the overhauled or replaced regulator from clogging up again.

About Motorhome Group

38,778 PostsLatest Activity: Jun 10, 2026