Problems caused by overfilled lpg tanks

[Dannyroger]

I ran the truck pretty low on gas the other day - switched to petrol when it started to lose power, which is emptier than I'd normally let it go.
After refilling, suddenly the engine won't idle on gas. Runs ok, but dies on idle. Been there before - checked leads and plugs and cleanout out Impco mixer and checked hoses and IAC etc etc - but no improvement.
Now, 60 km on and who knows exactly why, all is good again.
Then I remembered that the gas pump at the servo hadn't shut off at 60 odd litres and was still pumping at 70 or so when I turned it off manually. Could it be that my lack of idle was due to an overfilled gas tank?

[101RRS]

Most likely yes - if I fill my tank to the first click and I have no issues. However if I fill past the first click or run on petrol on a hot day rather than gas immediately after fill the truck will only run for a short distance on gas. I assume pressure is to much.

So now when I fill with gas I never go past the first click and I always run on gas for at least 10km before switching over - this seems to keep pressures all OK.

Garry

[Dannyroger]

Thanks Garry. I first thought it was maybe gunked up from running so low but the pressure thing makes sense - I think the 20% space is needed for the liquid LPG to pressurise meaning not enough space would be too much pressure.
Guess that means my automatic 20% cutter-offerer is cactus.

[Lotz-A-Landies]

It may also be a problem of the pump at the station, may require a service.