Outer Limits 4x4 Board

I have just completed a duel fuel conversion on my rangie and i'm having trouble tuning the gas system. I have a L G motor gas P2 converter and twin mixers mounted to my carbs, the converter has idle and another mixture screw and i have been tweaking both but just cant get it to idle or run smoothly off idle to about 1500 rpm. Its pops and backfires when i backoff over 1500 rpm but then when i get to about 60 + kph its smooth untill i back off again. I have regapped my plugs and checked the timing again and have recently fitted new 8mm top gun ignition leads.Any help will be much appreciated. I will upload a pic tomorrow.

Thanks,
Nick.

Sounds way too rich. Maybe one mixer would be fine for your setup, hence two is too rich. Maybe the adjustment for the lever off the diaphram. It needs to be just off it at idle. The whole system must suit your engine, not be near enough. Also, LPG is not really tunable "by the seat of your pants". You really do need it on proper computer setup for mixtures. Also, Top Gun leads are shit. Usable but shit. I have them too but there is better. Pay extra and get them from ICE in Moorabin. Having said that though, I'm not a guru but this info is from people who are, as I too have asked the exact same questions just recently as you.

Sounds way too rich. Maybe one mixer would be fine for your setup, hence two is too rich. Maybe the adjustment for the lever off the diaphram. It needs to be just off it at idle. The whole system must suit your engine, not be near enough. Also, LPG is not really tunable "by the seat of your pants". You really do need it on proper computer setup for mixtures. Also, Top Gun leads are shit. Usable but shit. I have them too but there is better. Pay extra and get them from ICE in Moorabin. Having said that though, I'm not a guru but this info is from people who are, as I too have asked the exact same questions just recently as you.

It could be rich but two mixers are needed due to being twin carbs, this is the type that is just a gas ring , there are no adjustments on them. I previously had an impco setup that was easy to tune but that was with a 350 holley.

My TB42 has one of those donut rings on it too but the converter and the inline adjuster still provide idle, coast and WOT adjustments. Of course you will need two rings due to twin carbs but are the rings small enough for a twin setup ie the one on mine will feed a 4.2 (not real sure on that though!) but two would be too big for yours let alone anything else if that makes sense? You might be doubling your fuel delivery. Is it coughing and spluttering like it is too rich under 1500rpm?

The mixers came off a another rangie and my mate has the same setup on his rangie with a different converter. Ideally i need to set the idle wot adjustments to a stock or medium setting and then work from there.

just a quick thought (incase its was as simple as mine to fix.)
i first thought my lux was running rich on gas,, same thing,, not happy under 1500 or so. so i would fuk around with the mixture screw on the mixer(impco) then gave it a few revs and stand behind it to see if my eyes water... (home made hc tester) did nothing.

found out because i had a vac leaks in a few different places, (i just though the motor was old, so had come to expect the power loss on petrol), but now it humms on gas at 800. and sweet as on petrol.

I think i may have it sussed, just need time to have a fiddle.

Loanrangie wrote:I think i may have it sussed, just need time to have a fiddle.

Yeah, that'll help you relax and think more clearly