Less Gas is Worse

[MMEJ]

Hi can anybody help? I have a v8 duel fuel 1996 Disco.Its done 245ks and is a manual. It runs fine on petrol and gas. but as the gas gets around half full and below it seems to run a bit lumpy and rough. No backfires or missing just dosnt seem to run as well as when the gas tank is full. Dont no if its to do with the gas system or thats just the way it is any answers would be helpful

[bee utey]

Some tanks develop cracks in the pickup pipe assembly that gets liquid LPG from the bottom of the tank. You may be running on vapour. If so your tank would get quite chilly/dewy to the touch as you draw vapour out of it. What sort of tank is it and where is it located? Pics are of course helpful.

[MMEJ]

The tanks are located under the rear of the Disco where the original fuel tank was I think There are two side by side hope the pics help Im no photo-genius

[ATTACH]Attachment 37959[/ATTACH]

[bee utey]

Yes these are APA tanks and have plastic pickup pipes. Not that I've seen them break in service, but there might be a pipe damaged during retesting. The pickup pipe can be accessed and repaired if necessary. First thing though, try opening the hand tap visible in the first picture, it looks closed.

[MMEJ]

Hi what will that do? will i have to turn it back? Should it be open at all times?

[MMEJ]

Hi thought I'd be brave went and tried gas tap, it is definatly open (screwed all the way out) Please ignore previous post I now understand. (gas tap shoud be open otherwise no gas comes out meanining car wont go duhhh)

[langy]

On the subject of gas taps - when the occasion to fill up arises, try running on one tank only - ie turn one off. If, after using half of it the same symptoms arise, turn it off and use the other one. That should indicate whether it's a tank fault ( L or R ) or converter/mixer problem. Also helps to make sure the electrical connections for the cut off solenoids are in good order. I've had a solenoid go dodgy when I had my LPG RRC.