Generator run issue

[dirtroad2]

I have a 98 Monaco Diplomat with a Onan 6.5 Lp genarator. My issue is that when I start the generator it starts and runs fine as long as the Lp tank is completly full. As soon as the LP tank gets to about 3/4 full the generator shuts down and does not get LP fuel. there must be some way to adjust the LP line level in the LP tank so it will run longer. like till the LP tank gets to 1/4 full or so. Any suggestions?

[dirtroad2]

My generator uses Liquid propane. I took the motor home and had the propane tank filled thinking the gauges may be wrong. The tank was only down 1/4 so the tank was 3/4 full. After he topped off the tank the generator started up and runs fine. My guess is that when the tank gets to 3/4 full again the generator will quit.I will have to keep looking as to why I am not getting liquid propane to the generator after I use 1/4 tank of propane. I also learned that the gauges are accurate.

[wolfe10]

BOTH liquid and vapor LP generators are out there-- we had a liquid 6.3kW Onan on our 1993 Foretravel. Most today are vapor.

Liquid LP generators will have a separate (lower/liquid) port on the LP tank. Vapor will T off the upper/vapor port on the LP tank.

[SaltiDawg]

eHoefler wrote:
RV Generators use vapor

And yet MrWizard posted before you saying his Onan used liquid.

[jplante4]

My Safari uses liquid. 2 valves.

[Chris_Bryant]

eHoefler wrote:
RV Generators use vapor

Most, not all- quite a few use a separate service valve for liquid.

[eHoefler]

RV Generators use vapor

[SaltiDawg]

dirtroad2,

Was the answer that your generator uses liquid propane and it was a valve line-up issue?

OR???

[eHoefler]

Comparing to tanks that lay on there side, motor coach, residential, etc.. As you draw vapor, the liquid will cool down as it boils off, thus slowing the evaporation of the liquid.

[SaltiDawg]

eHoefler wrote:
You are drawing more gas than can boil off to vapor. Small tanks are very prone to freeze up. Not enough surface area on the liquid to allow boiling of to vapor...

What shape tank has less surface area at 3/4 full than at full? :h

[eHoefler]

You are drawing more gas than can boil off to vapor. Small tanks are very prone to freeze up. Not enough surface area on the liquid to allow boiling of to vapor. You may need to install a magnetic heater to the tank to help with it to vaporize the liquid. Propane boils at -44*, cooler the ambient temperature is, the slower propane will boil off. If the tank is very cold and has condensation or frost on it, chances are it is too cool for the propane to boil off and maintain the pressure for the draw required.

[MrWizard]

how many valves are on the tank one or two
if two, the Onan is liquid feed, make sure the bottom valve is open

my Onan is liquid feed
1995 Safari

[dirtroad2]

stove, furnace, fridge,all work fine. just the gen does not run when level drops

[KD4UPL]

Most LP generators run on vapor, not liquid LP. If yours is the same and runs on vapor then the gas will be coming out of the tank under pressure. There's no line to adjust.
How long has it been since the air was purged form your tank? Have you checked the pressure at the output of your regulator?