Hi, I've been scratching my head over this for a while now, no matter what I do I cannot get my system to do anything other than run lean. I will also say it's just above full lean at idle and then lean for every other driving condition.
My set-up in the old Series 3 88" is as follows:
Lovato Tank, switch/gauge, and filter
OMVL R90 vaporiser
Blos carb
Lambda sensors in each down pipe connected to a Air/Fuel ratio gauge
3.9 Disco 1 engine with injection manifold and plenum, but injectors disconnected.
So far I've:
Checked for air leaks and am happy there are none
Replaced the sparkplugs for standard NGK ones
Replaced the dizzy cap
Replaced the rotor arm
Replaced the plug leads
Re-timed the engine to about 22 deg advance, vacuum disconnected
Put a recon kit in the OMVL vaporiser
Replaced the LPG filter
Fitted the BLOS carb in place of the original twin SU set-up with mixer plates
Everything is set to maximum fuel delivery yet the thing runs lean, there is no misfire and the engine feels very strong when you drive it. I've not dismissed the fact that the two eBay special Lambda sensors could be at fault, or do not work correctly with LPG.
Is there anything else in the system that could be reducing the fuel flow to cause this? Or am I missing something here?
As a simple test, I put my propane blow lamp into the air intake to feed extra LPG into the engine on top of what was being delivered by the standard system. This isn't a little blow lamp, its a separate torch and big 19kg orange bottle, I had the thing pretty much full on to get the Air/Fuel ratio gauge to read somewhere near correct at idle. That's a lot of LPG going in, the engine rpm increased a little, but not much.
My set-up in the old Series 3 88" is as follows:
Lovato Tank, switch/gauge, and filter
OMVL R90 vaporiser
Blos carb
Lambda sensors in each down pipe connected to a Air/Fuel ratio gauge
3.9 Disco 1 engine with injection manifold and plenum, but injectors disconnected.
So far I've:
Checked for air leaks and am happy there are none
Replaced the sparkplugs for standard NGK ones
Replaced the dizzy cap
Replaced the rotor arm
Replaced the plug leads
Re-timed the engine to about 22 deg advance, vacuum disconnected
Put a recon kit in the OMVL vaporiser
Replaced the LPG filter
Fitted the BLOS carb in place of the original twin SU set-up with mixer plates
Everything is set to maximum fuel delivery yet the thing runs lean, there is no misfire and the engine feels very strong when you drive it. I've not dismissed the fact that the two eBay special Lambda sensors could be at fault, or do not work correctly with LPG.
Is there anything else in the system that could be reducing the fuel flow to cause this? Or am I missing something here?
As a simple test, I put my propane blow lamp into the air intake to feed extra LPG into the engine on top of what was being delivered by the standard system. This isn't a little blow lamp, its a separate torch and big 19kg orange bottle, I had the thing pretty much full on to get the Air/Fuel ratio gauge to read somewhere near correct at idle. That's a lot of LPG going in, the engine rpm increased a little, but not much.
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