Fiat 903 CC Automobile User Manual


 
plate should be open (dimension A) (Fig. 3.1 2)
between 0.75 and 0.80 mm (0.030 and
0.032 in). Adjust if necessary by means of the
screw and locknut.
Anti-flooding device
11 This consists of a diaphragm capsule and
link rod.
12 The condition of the diaphragm can be
checked by applying a vacuum source to the
hole in the throttle valve plate block. The
vacuum pressure will drop if there is a leak.
13 Actuate the choke valve plate lever fully
and depress the control lever of the
anti-flooding device to simulate operating
vacuum.
14 There should be a gap (Y) (Fig. 3.15)
between the edge of the choke valve plate
and the wall of the carburettor throat of
between 3.75 and 4.25 mm (0.148 and
0.167 in). Any adjustment that may be needed
should be carried out by bending the link rod.
10 Carburettor
(Solex C32 DISA 11) -
servicing and adjustment
4
1 The carburettor top cover with float may be
removed without the need to withdraw the
carburettor from the manifold. The other
adjustments described will require removal of
the carburettor.
2 Extract the top cover fixing screws,
disconnect the small externally mounted
tension spring and take off the top cover.
3 Access to the fuel inlet needle valve is
obtained by carefully tapping out the float arm
pivot pin. Take care, the pivot pin pillars are
very brittle.
4 Check that the needle valve body is tight
otherwise fuel can bypass the needle valve
and cause flooding.
Float adjustment
5 Reassemble and check the float setting. Do
this by inverting the top cover so that the
weight of the float fully depresses the ball of
the needle valve. The distance (A) (Fig. 3.16)
between the float and the surface of the top
cover flange gasket should be between 2.0
and 3.0 mm (0.079 and 0.118 in). If
adjustment is required, alter the thickness of
the washer under the needle valve.
Accelerator pump
6 Fill the carburettor float chamber and then
operate the throttle valve plate lever several
times to prime the pump.
7 Position a test tube under the accelerator
3•8 Fuel system
Fig. 3.16 Float setting diagram
(Solex C32 DISA 11) (Sec 10)
A = 2.0 to 3.0 mm (0.079 to 0.118 in)
Fig. 3.17 Adjusting accelerator pump rod
(Solex C32 DISA 11) (Sec 10)
Fig. 3.15 Choke valve gap opening
(Weber 32 ICEV 50/250) (Sec 9)
Y = 3.75 to 4.25 mm (0.148 to 0.167 in)
Fig. 3.14 Anti-flooding device vacuum
intake (Weber 342 ICEV 50/250) (Sec 9)
1 Vacuum intake hole
Fig. 3.12 Fast idle adjustment diagram (Weber 32 ICEV 50/250)
(Sec 9)
A = 0.75 to 0.80 mm (0.030 to 0.032 in)
Fig. 3.13 Anti-flooding device (Weber 32 ICEV 50/250)
(Sec 9)
Y = 3.75 to 4.25 mm (0.148 to 0.167 in)