V8 3.9 fuelling problem?

My first post so go easy on me. It's a dual fuel 1986 Defender 90 with a Disco 3.9 Weber / Edelbrock carb 1992 engine and high lift cams. Symptom is crap starting on petrol, but runs fine after a squirt of 'Please Start'. It then runs fine on petrol and LPG, although a little sluggish on hills. I'm looking at the fuel system and replaced the tank and pump which needed it anyway, but still same symptom. Next I'll have a look at the fuel filter. However, I'm interested in knowing what the little barrel on the fuel return system is (see pic) - is it a simple empty chamber that the carb floats control or is it something more complicated? I can't seem to find any info on the net about it. I'm also considering advancing the timing a little to see if it affects performance.
Any help appreciated
Martin MacGillivray

Welcome to LandyZone

(after 6 years )

Hello and welcome

Thank you for your welcome! Have I posted this thread in the correct place?

The best solution for running dual fuel is a smart box produced by RPI engineering. It allows you to set timing for petrol and automatically changes it when you switch to LPG. Timing is usually advanced for LPG because it burns slower. I had this set up on a classic RR this way you get optimum performance for either fuel.
Note this is for carb conversion setups not multipoint lpg systems

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