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ENGINE CHANGEOVER TO GAS
If the engine does not change smoothly to gas, adjust the potentiometers on the FP50 as follows;
8.
Fine Adjustments to the PETROL OVERLAP Potentiometer
The FP50 contains an internal relay (with normally closed 10 amp contacts). This relay will turn the
petrol injectors off when operating on gas. A short (adjustable) overlap is provided to ensure a
smooth transition from petrol to gas. This helps to prevent back-firing due to lean mixtures. The
FP50 may also contain an optional in-built current controlled injector emulator. This will satisfy the
many engine management systems (but not all). If you experience dashboard engine
management error lights, please contact your local distributor for more information.
FP50-DS-SS (Changes to LPG/CNG during Cranking)
If the engine is difficult to start, observe the green
Gas
light and the red
Petrol
light. If the
Petrol
light goes out
before
the engine has properly started, turn the PETROL OVERLAP
potentiometer a little more towards the arrow (for more petrol start). If the engine appears to
start and then stalls while the
Petrol
light remains on, turn the PETROL OVERLAP
potentiometer slightly away from the arrow (for less petrol start). This procedure may need to be
done several times to ensure easy starting is achieved. Remember that slightly more petrol start
is required after the vehicle has been left overnight.
Don't forget to plug the hole with the plastic
stopper to prevent water entry.
FP50-DC (Changes on Deceleration) & FP50-AC (Changes on Acceleration)
If the actual changeover from Petrol to Gas is not smooth, the PETROL OVERLAP
potentiometer will need to be adjusted. Observe both the
Petrol
and the
Gas
lights during the
changeover to gas. If the engine loses power as soon as the
Petrol
light goes out, turn the
PETROL OVERLAP potentiometer slightly towards the arrow (for increased petrol overlap). If
the engine loses power when the
Petrol
light is still on, turn the PETROL OVERLAP
potentiometer slightly away from the arrow (for reduced petrol overlap). This procedure may
need to be done several times to ensure you arrive at a comfortable PETROL OVERLAP time.
Don't forget to plug the hole with the plastic stopper to prevent water entry.
9.
Fine Adjustments to the TPS/RPM SET Potentiometer
FP50-DS-SS
With the engine running, check that the green ACCEL TPS SET light flashes quickly at idle and
stops flashing when you
slightly
depress (and hold) the accelerator (assuming you wish to run
the preferred Open Loop option at idle).
Don't forget to plug the hole with the plastic stopper to
prevent water entry.
FP50-DC & FP50-AC
If the changeover to gas occurs when the engine revs are too low, adjust the TPS/RPM SET
potentiometer slightly towards the arrow (this sets a higher TPS changeover voltage). If the
changeover to gas occurs when the engine revs are too high
(or you cannot changeover the
vehicle to gas at all)
, adjust the TPS/RPM SET potentiometer slightly away from the arrow
(this sets a lower TPS changeover voltage). This procedure may need to be done several times
to ensure you arrive at a comfortable TPS/RPM changeover point.
Don't forget to plug the hole
with the plastic stopper to prevent water entry.
10.
Turn off the engine. Connect the CV30/CE Stepper Valve for the very first time.
Summary of Contents for FP50 Series
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