backfiring on lpg system will happen from time to time if, as i suspect, its a single point system. so a ignition system check/overhaul will be necessary and also check the vapourizer is not the hicghest point on the cooling system as this can lead to airlocks and rr's dont like airlocks or overheating!!
Beast o Bodmin
Banned
clean and waxoyl the baulkhead and pillars that hold the door hinges.When i mean clean i mean CLEAN .Inside the body work too.Strip the interiour out and see what you find if you want to keep it.
Trust me we can get round anything! Just trying to find out common things we hadn't thought of.
Mine's a single point system and has never backfired, is this a fault with RRs and are defenders exempt.
What makes them backfire anyway, something must be wrong, a leak or something surley or am I misinformed.?
I had a single point system on a 3.9 auto discovery and for an unknown reason if you engaged the LPG while in gear and driving, it made a loud bang and sucked a flap near the AFM back on itself (i forget what the flap was called). Used to have to manually full the flap back and was ok after that. In the end if I wanted to engage the LPG going along i had to put it in neutral then gently rev it to change it over. Never did get to the bottom of it.
the backfiring can be caused by many things but it is usually the fact that there is lots of gas in the intake that causes it to be so dramatic. on my p38 it was a dodgy gas ring that wasnt sealed to the plenum fully and allowing the mixture to be random, then when it did backfire it blew the gas ring off and stalled the car!!
got round that by permanently sealing the gas ring to the plenum.
also make sure the lpg vapourizer is not above the water level as this could result in the gas vap freezing due to an air lock. it's usually easy to lower the vap. for some reason it was never thought of when lpg was installed on many cars!!!
got round that by permanently sealing the gas ring to the plenum.
also make sure the lpg vapourizer is not above the water level as this could result in the gas vap freezing due to an air lock. it's usually easy to lower the vap. for some reason it was never thought of when lpg was installed on many cars!!!
Depends I think on the individual systems.
I've had a single point lpg system on my 92 Classic from when I bought it in Jan 08 and it was fitted in 2004.
Never had a problem with backfires.
It sometimes stalls when switching to gas while on the move not always but better to do at lights in neutral and then just give a few gentle revs, if it does stall then at least I can start it again easily which it does every time. Not really an issue for me.
I've had a single point lpg system on my 92 Classic from when I bought it in Jan 08 and it was fitted in 2004.
Never had a problem with backfires.
It sometimes stalls when switching to gas while on the move not always but better to do at lights in neutral and then just give a few gentle revs, if it does stall then at least I can start it again easily which it does every time. Not really an issue for me.
depending on the system(probably a leonardo controller) you can get software for it and reset the settings/tune the controller. do save the current settings tho as you can at least restore without any harm done.
let me know which controller you have and i'll post a link to it if i have it!!
let me know which controller you have and i'll post a link to it if i have it!!
al-one-arm
Well-Known Member
mines a leonardo single point, never had any problems with it, but it would be very handy to be able to save the settings, so that if i disconnect battery at any time(it loses all settings) , i can get it back running on gas easily, without the customary £40 reset charge
