1987 SUZUKI GRAND VITARA Service Repair Manual

2) Remove air horn from float chamber after
disconnecting three hoses and pump lever and
removing five screws of air horn. Loosen idle
up bracket screw.
3) Remove float and needle valve from air horn
and then needle valve seat and filter.
1. Air horn
2. Needle valve seat
3. Needle valve filter1. Air horn3. Pump lever2. Hose4. Screw
Fig. 4- l-22 Needle valve seat and filterFig. 4- l-20 Air horn and hoses, etc.
NOTE:
Never loosen 4 screws fixing element holder at
this point.
4) Remove micro switch bracket after removing
2 springs and 2 screws indicated in below
figure.
NOTE:
Don’t remove micro switches from bracket.
1. Therm0 element holder
2. ScrewFig. 4-l-21
1. Micro switch bracket
2. Spring
3. Screw
Fig. 4- l-23 Idle and wide open micro switches
and bracket
4-14

5) Remove two drain plugs and then primary
and secondary main jets in float chamber
through plug’s holes, using a negative screw
driver.
1. Drain plug
Fig. 4- l-24 Drain plugs
6) Remove throttle chamber from float chamber
after removing four screws shown in below
figure.
1. Throttle chamber
2. Screw
Fig. 4- l-25 Throttle chamber
Cleaning
1) Wash below listed items in carburetor cleaner
and then clean them by blowing compressed
air.
l All removable air jets and fuel jets, except
mixture control solenoid valve jet.
l Needle valve, valve seat and filter.
2) Blow compressed air into all passages to
clean.
3) Clean bottom of float chamber.
NOTE:
1) Don’t immerse following parts in carburetor
cleaner.
l Micro switches (wide open switch and idle
switch)
l Switch vent solenoid
l Fuel cut solenoid valve
l Mixture control solenoid valve
l Secondary diaphragm, choke piston and
idle-up actuator
l Parts made of rubber or resin and gasket
l Thermo-wax (therm0 element)
2) Don’t put drills or wires into fuel passages
and metering jets for cleaning. It causes
damages in passages and jets.
3) If cleaning solvent contacts rubber or resin
parts, be sure to blow off cleaning solvent by
compressed air immediately.
Inspection
1) Check choke va’lve and throttle valves for
smooth operation.
2) Check rubber cup of pump piston and seal of
mixture control solenoid valve for deteriora-
tion and damage. Refer to below figure.
3) Check needle valve and valve seat for wear.
1. Mixture control solenoid valve
2. seal3. Spring4. Rubber cup
Fig. 4- l-26 Accelerator pump piston and mixture
control solenoid valve
4-15

Assembly
1) Install insulator to float chamber as shown in
below figure.
1. Float chamber
2. Insulator
Fig. 4- l-27 lnsula tor installation
2) After attaching both ends of throttle lever
return spring as shown in figure, install
throttle chamber to float chamber. Hook
throttle valve side end of return spring over
the boss on float chamber as shown in below
figure.
3) Install spring washer as below figure, and
torque four screws to specification.
Tightening torque
for screws
4-7 N-m
0.4 - 0.7 kg-m
3 - 5 lb-ft
1. Throttle chamber
2. Spring washer
Fig. 4- l-29 Installing washer
4) Install primary and secondary main jets.
1. Float chamber2. Boss3. Throttle lever return spring
4. Throttle chamber
Fig. 4- l-28 Hooking throttle lever return spring
1. Primary main jet
2. Secondary main jet
Fig. 4-I-30 Primary and secondary main jets
4-16

5) Install gaskets and drain plugs, after installing
main jets.
1. Drain plug
Fig. 4- l-3 1Installing drain plugs
6) Install level gauge seal.
chamber
2. Level gauge seal
Fig. 4-l-32 lnstalling.level gauge seal
7) install micro switch bracket with micro
switches and level gauge, and two springs
as shown in below figure.
NOTE:
0
0
Don’t remove micro switches (idle switch &
wide open switch) from bracket.
When bracket with micro switches has been
removed from float chamber for any service
and reinstalled after service work, make sure
to check switches for operation and adjust
if necessary. Check and adjustment for micro
switches should be carried out with carbure-
tor removed from intake manifold.
Refer to SECTION 5 “EMISSION CONTROL
SYSTEM” for procedure to check and adjust
micro switches.
1. Micro switch bracket
2. Spring3. screw
Fig, 4- l-33Ins tailing bracket and springs
8) Install jets and air bleeders to float chamber.
Refer to Fig. 4-l -34 for their installation.
1.Primary slow air No. 2 bleeder
2.Primary slow jet
3.Primary main air bleeder
4.Secondary main air bleeder
5.Secondary slow jet
Fig. 4- l-34Installing jets and air bleeders
4-17

9) Install balls, injector spring and weights to
accelerator pump. Direct “U” bent end side
of piston return spring downward as shown in
below figure.
3
2. Piston return spring3. “U” bent end4. Injector spring5. Injector weight
Fig. 4- l-35Ins tatting balls, in jet tor spring and
weights, and piston return spring
10) Install needle valve filter, valve seat, gasket,
needle valve and float to air horn. After
installing float, check for float level and
adjust if necessary.
11) Install primary and secondary slow air
bleeders to air horn.
1. Primary slow air No. 1 bleeder
2. Secondary slow air bleeder
Fig. 4- l-36 Installing slow air bleeders
12) Be sure to apply silicone oil to mixture
control solenoid valve seal before installing
air horn to float chamber.
NOTE:
Be sure to use silicone oil that will not affect
rubber.
1. Mixture control soelnoid valve
2. Seal
Fig. 4- l-37 Mixture control solenoid valve seal
13) Install air horn gasket to float chamber. Use
new gasket.
14) Install air horn to float chamber. After
installing acceleration pump lever to air
horn, check lever for smooth operation.
15) Connect 3 hoses as shown below figure.
I, Choke piston hose
2. Secondary diaphragm hose
Fig. 4- l-38 Installing hoses
4-18

16) Clamp wire harness securely.MAINTENANCE SERVICES
Fig. 4- l-39
1. Clamp
17) Remove the pin installed before disassemb-
ly (to lock fast idle cam).
Fig. 4- l-40
Before checking or adjusting the carburetor as
the cause of poor engine performance or rough
idle, check the followings for malconditions.
Ignition system including distributor, timing,
spark plugs and wires.
Air cleaner including thermostatically control-
led air cleaner system.
Evaporative emission control system.
PCV system.
EG R valve.
Engine compression.
Also, check the intake manifold, carburetor and
vacuum hoses for leakage.
Accelerator Cable Adjustment
Check accelerator cable for play and adjust if
necessary.
Cable play should be within the specifications. If
out of specification, loosen lock nut and adjust
by turning adjusting nut. Be sure to tighten lock
nut securely after adjustment.
Condition
When carburetor and
coolant are cold;
When carburetor and
coolant are warm;
Cable play
10 - 15 mm
(0.4 - 0.6 in.)
3-5mm
(0.12 - 0.20 in.)
1. Accelerator cable
2. Cable play
3. Lock nut
4. Adjusting nut
Fig. 4- l-4 1 Accelerator cable play
4-19

Float Adjustment
l)The fuel level in float chamber should be
within round mark at the center of level
gauge.
1. Level gauge
2. Round mark3. Fuel level
Fig. 4- l-42 Fuel level
2) If the fuel level is not found within the round
mark, check the float level and adjust it as
follows:
a) Remove the air horn, and invert it.
b) Measure the distance between the float and
the gasketed surface of air horn. The
measured distance is float level, and it
should be the specification.
If the float level is out of specification,
adjust it by bending the tongue up or
down.
NOTE:
l This measurement should be made without a
gasket on the air horn.
l Check float height with float weight applied
to needle valve.
l As a gauge for checking float level, use
something whose thickness measurement is
the same as specified level measurement
(such as a drill or M8 bolt) after confirming
thickness with vernier calipers.
Float level8mm
specification(0.31 in.)
.
Fig. 4- l-43 Float level
1. Air horn
2. Float
3. Float level
4. Tongue
Idle Up Adjustment
1) Warm up engine to normal operating tempe-
rature.
2)Check to be sure that engine idle speed is
specification.
3) Check to ensure that idle-up actuator rod
moves down (indicating that idle-up is at
work) when small light, tail light, license
light and side marker light are turned “ON”.
1. Idle-up actuator
2. Idle-up actuator rod
3. Choke piston
4. Idle up adjustingsorew
Fig. 4- l-44 Idle-up adjusting screw
4-20

4) With lights (head light) turned “ON”, check
engine rpm (idle-up speed). Be sure that
heater fan, rear defogger (if equipped), and
air conditioner (if equipped) are all turned
“OFF”.
Idle-up speed900 - 1,000 r/min.
If idle-up speed is not within specification,
adjust by turning adjusting screw.
5) After idle-up adjustment, check to ensure that
idle-up adjusting screw moves as in step 3)
when only heater fan is operated and then
only rear defogger is operated (small light, tail
light, side marker light and license light should
be “OFF” in this cases).
If found faulty in step 3), check following parts
individually according to each procedure.
[Checking TWSV]
1) Make sure that lighting switch, heater fan
switch, rear defogger switch (if equipped) and
air conditioner switch (if equipped) are all
turned OFF.
2) Disconnect TWSV vacuum hoses from intake
manifold and actuator.
With ignition switch at “OFF” position, by
blowing air into hose disconnected from
actuator, make sure there is no continuity
between these hoses.
Turn lighting switch to ON position and by
blowing air into the hose disconnected from
actuator, make sure that there is continuity
between hoses.
Fig. 4- l-45
1. TWSV (Black)2. To intake manifold3. To actuator
[Checking TWSV circuit]
1) Warm up engine to normal operating tempe-
rature.
2) Stop engine and disconnect TWSV coupler.
3) Run engine at idle speed and connect volt-
meter to coupler terminals disconnected.
Check that voltmeter indicates OV.
4) Check that voltmeter indicates about 12V
under either of the following conditions.
0 When engine speed exceeds 2,000 r/min.
l When lighting switch, heater fan switch or
rear defogger switch (if equipped) is turned
ON.
If defective in steps 3) and 4), the particular
circuit is disconnected or in poor contact.
Check the circuit for such condition. For detail,
refer to item “CHECKING IDLE UP SIGNAL”
in SECTION 5 “EMISSION CONTROL SYS-
TEM”.
Fig. 4- l-46
[Checking actuator]
1) Disconnect hose from TWSV.
2) Connect special tool (vacuum pump gauge) to
its hose,
3) Check that actuator rod moves smoothly and
that it is held at the same position when
about 40 cmHg vacuum is applied to actuator.
If rod doesn’t move smoothly, or it isn’t held at
the same position, replace actuator.
If defective in steps 3) and 4), replace TWSV or
checking TWSV circuit.
4-21