Mixture Setting - Lotus TURBO ESPRIT Service Manual

Page 6
SECTION EMA
Allow engine to reach normal runniLg temperature
i
.e. o i l and coolant should
be stabilised.
5 .
i)
.
ii).
...
1 1 1 ) .
iv)
.
+
Ad just idle speed to
950
-
50
rpm
.
+
0
Adjust ignition timing to
lo BTDC
-
1
.
Check carburettor balance a t manometer. Check that a l l
4
columns
are balanced within 3mm,
i f
not re-balance the carburettors. (see
Carburettor Balancing Procedure).
Check fuel pressure at the regulator
-
this should be lower than 3.5
psi
at idle.
If
the pressure i s higher the micro switch position on the front
carb bracket w i l l require adjustment
.
Rotate the switch down towards the
lever until switch contact i s made. Manifold pressure w i l l now be
connected to the fuel regulator via the regulator solenoid.
6.
Mixture setting
-
with the carbs balanced and rpm and fuel pressure set, the idle
mixture can be sampled and adjustment made
if
required.
i).
Switch analyser to sample mode and check readihgs.
NOTE:
Do not touch idle adjustment screws until
CO
reading has
stabil ised
.
The carburetton have been flow tested and only minor
adjustment w i l l be required,
i f
any.
i i )
.
CO
reading should be within
0.2
to
1 -2%. If
higher or lower levels are
found, remove anti-tamper plugs and move each mixture screw a
4
of a
turn i n or out as the reading dictates, check the C O reading and repeat
until the tune specification i s reached.
A
balance between
CO
and HC
i s required and the hexane level should be below 550 ppm for a 'new
engine' and below 350 ppm for a run-in engine. When adjustment
i s
complete f i t anti-tamper plugs
.
CROSS SECTION THROUGH AN71 TAMPER IDLE CO A Y v S T E R
IDLE CO ADJUST'
CARBURE TTOR
ENGINE IDLE
SPEED SCREW-
IDLE S l W BRACKET
FRONT
OF
VEHICLE
I
L