LANDI RENZO S.p.A.
‘SE 81 SIC’ LPG REGULATORS INSTALLATION AND ADJUSTMENT MANUAL
9 / 19
Regulators setting
4.3 CARBURETTED CAR
The first step is to adjust peak speed:
• take the engine to approximately 3,500 r.p.m.
and turn the peak speed regulator, located
between the regulator and the mixer, to take the
values of CO, HC and CO
2
as shown in the table.
The second step is to adjust idling speed:
• with the engine running, turn the Idle speed
setting screw (E) (clockwise it decreases,
anticlockwise it increases) to take the values of
CO, HC and CO
2
as shown in the table.
Having regulated idling and peak speeds, carry
out a test on the road.
SETTING TABLE ‘SE 81 SIC’
GAS
SPEED
LIMITS
bottom
top
CO (in %)
idling
1.25
1.50
3.500 g/m
0.30
0.60
CO
2
(in %)
idling
12
14
3.500 g/m
13
15
HC (in ppm)
idling
100
150
3.500 g/m
20
60
5. SETTING PROCEDURE FOR REGULATORS
TYPE ‘SE 81 SIC’
without exhaust gas analyser
(Fig. 1)
5.1 CATALYSED CAR
See point 4.1 without gas analyser check.
5.2 INJECTION AND CARBURETTED CAR
The first step is to adjust peak speed:
• take the engine to approximately 3,500 r.p.m.
and turn the peak speed regulator located
between the regulator and the mixer clockwise
until you notice a fall in engine speed due to the
mixture getting leaner; then turn this same screw
very slowly anticlockwise until there is an increase
in engine speed; at this stage it is not necessary
to turn the screw further anticlockwise since there
would only be greater consumption and no
increase in efficiency.
The second step is to adjust idling speed:
• with the engine running, turn the Idle speed
setting screw (E) (clockwise it decreases,
anticlockwise it increases) until an optimum idling
Sensitivity setting
speed is obtained which is also to be checked
after the road test.
Having regulated idling and peak speeds, carry
out a test on the road.
6. SENSITIVITY SETTING PROCEDURE FOR
REGULATORS TYPE ‘SE 81 SIC’
(Fig. 1)
The regulators are already set in-house by the
manufacturer. If problems arise, such as idle
speed instability or acceleration gap, please check
the degree of regulator sensitivity.
The setting screw (G) is not used for setting idle
speed but simply to adjust the regulator sensitivity.
By unscrewing it you reduce the spring load on the
2nd stage lever while by tightening it you increase
the spring load on the 2nd stage lever towards
closing.
In particular, since the idle speed flow is
separated from the peak speed one, shifting from
idle to peak speed should take place without
‘carburation gaps’; such gaps may occur, above
all, during too slow accelerations (too tightened
screw); at the same time the regulator should
remain tight without any gas leakage every time
the engine is turned off (too loose screw).
In order to set sensitivity as required do as
follows:
1) Remove the tube which conveys gas from
the gas outlet connector to the mixer (C);
2) Tighten the sensitivity screw (G);
3) Disconnect the blue wire from the plus
contact of the idle speed solenoid valve (F)
and connect the same wire to the plus
contact of the battery ( in order to fill with gas
the regulator);
4) Make a bubble with soap water on the gas
outlet connector (C) and loosen the screw
(G) until the gas starts coming out of the
regulator and inflates the bubble;
5) From the time gas starts coming out of the
regulator, tighten screw (G) again until no
more gas leaks. From the moment that no
more gas leaks, tighten the screw another
half turn to be sure that it closes perfectly;
6) Connect again the blue wire to the plus
contact of the idle speed solenoid valve (F);
