FIAT Uno 45 - Manual (Page 187)

PART B:
CARBURETTOR MODELS
Carburettor (Weber 32 TLF) -
description
Warning: Refer to the beginning
of this Section before starting
any work.
1 This carburettor is used on the 999 cc
engine and is of the single venturi
downdraught type, with a manually-operated
choke (cold start).
2 The unit incorporates an automatic
anti-flooding device, a full power valve and an
accelerator pump (photos).
3 The throttle valve block, although
incorporating coolant hose stubs, is not in fact
coolant-heated.
4 A solenoid-operated idle cut-off valve is
fitted to prevent running-on (dieseling) when
the ignition is switched off.
Carburettor (Weber 32 TLF) -
idle speed and mixture
adjustment
¢
5 If the car is not equipped with a rev counter,
connect one in accordance with the
manufacturer’s instructions.
6 Have the engine at normal operating
temperature and idling. Turn the idle speed
screw on the carburettor until the speed
matches that specified (photo).
7 The idle mixture is set in production, and
the adjustment screw is sealed with a
tamperproof cap. If, however, the idling is not
smooth or the engine or carburettor have
been extensively overhauled, the mixture may
require adjusting.
8 Prise out the tamperproof plug and connect
an exhaust gas analyser to the car in
accordance with the instrument
manufacturer’s instructions (photo).
9 With the engine at normal operating
temperature and idling at the specified speed,
turn the mixture screw until the CO
percentage is within the specified tolerance
(photo).
10 If an exhaust gas analyser is not available,
turn the mixture screw anti-clockwise to
obtain maximum idle speed and then turn it
clockwise until the speed just starts to drop.
Re-adjust the idle speed screw to bring the
idle speed to the specified level.
11 Switch off the engine and remove the test
instruments. It is advisable to fit a new
tamperproof cap to the mixture screw if it is
intended to take the vehicle overseas. This is
required to meet legislation in certain
countries.
Carburettor (Weber 32 TLF)
- removal and refitting
™
12 Remove the air cleaner.
13 Release the clips and disconnect the fuel
hoses from the carburettor. Take extreme
care that fuel spillage is contained and that
there are no naked flames in the vicinity of the
work area. Do not smoke.
14 Disconnect the distributor vacuum hose
from the carburettor.
13•62 Supplement: Revisions and information on later models
9B.9 Mixture adjustment - Weber 32 TLF
carburettor
9B.8 Weber 32 TLF 4/250 carburettor
mixture screw location under tamperproof
plug (arrowed)
9B.6 Weber 32 TLF 4/250 carburettor idle
speed screw (arrowed)
9B.2E Weber 32 TLF 4/250 carburettor
from above
9B.2D Weber 32 TLF 4/250 carburettor
from throttle linkage side
9B.2C Weber 32 TLF 4/250 carburettor
from accelerator pump side
9B.2B Weber 32 TLF 4/250 carburettor
from choke linkage side
9B.2A Weber 32 TLF 4/250 carburettor
from anti-run-on solenoid valve side