1987 SUZUKI GRAND VITARA fuel filter

4-3.FUEL PUMP, FILTER AND LINES
GENERAL DESCRIPTION
The main components of the fuel system are fuel tank, fuel pump and fuel filter and it includes three
lines; fuel feed line, fuel return line and fuel vapor line.
Fig. 4-Z-5
4-31

Fuel Pulp
A mechanical fuel pump is mounted on the
cylinder head.
The diaphragm in fuel pump is actuated from
the cam on the engine camshaft, through a fuel
pump rod and a rocker arm of fuel pump. A
rocker arm rides on the cam through the fuel
pump rod and moves the pump diaphragm up
and the fuel pump feeds the fuel into carburetor.
A fuel return circuit is provided in this pump in
order to avoid “vapor lock”. When the float
chamber refuses to admit fuel, a slight pressure
buildup occurs on the discharge side of the
pump and this buildup causes the fuel to flow
through the return circuit to the fuel tank. In
other words, the fuel pump is kept in action as
long as the engine is running, so that the con-
stant flow of fuel through the pump keeps it
cool.
2
Fig. 4-2-8
Fig. 4-2-6
Fuel Filter
Fuel filter is located at the front part of fuel
tank, inside the right-hand side of chassis.
Fuel enters the filter through its inlet hose and,
after passing through filtering element, comes
out of its outlet hose communicated to the fuel
pump. This filter is not meant to be disassem-
bled. It is of cartridge type, consisting of a
filtering element in a plastic case.
1
1. Fuel pump
2. inlet hose
3. Outlet hose4. Return hose
6
1. Inlet
2. Outlet
Fig. 4-2-9
1.Inlet
2.Outlet
3.Return tube
4.inlet valve
5.Outlet valve
6.Diaphragm
7.Rocker arm
8.Fuel pump rod
Fig. 4-2-7
4-32

,Fuel Pump
[ Rem’oval]
1) Disconnect negative cable from battery.
2) Remove fuel filler cap from fuel filler neck to
release fuel vapor pressure in fuel tank. After
releasing, reinstall the cap.
3) Disconnect fuel inlet, outlet and return hoses
from fuel pump.
Fuel Filter
[Removal]
1) Disconnect negative cable from battery.
2) Remove fuel filler cap to release fuel vapor
pressure in fuel tank. After releasing, reinstall
the cap.
3) Disconnect inlet and outlet hoses from fuel
filter.
4) Remove fuel filter with clamp.
[Installation]
1) Install filter and clamp, and connect inlet
and outlet hoses to fuel filter.
NOTE:.
The top connection is for outlet hose, the
lower one for inlet hose.
1. Fuel pump
2. Inlet hose3. Outlet hose
4. Return hose
Fig. 4-2-l 1
4) Remove fuel pump from cylinder head.
5) Remove fuel pump rod from cylinder head.
2
1. Fuel pump rod
2. Cylinder head
[Installation]
Reverse removal procedure for installation
using care for the following.
l After oiling it,install fuel pump rod to
cylinder head.
0 Use new fuel pump gasket.
l Make sure for proper hose connection.
0 Upon completion of installation, start engine
and check fuel hose or its joints for leaks.
1.Fuel filter3.From fueltank
2.To fuel pump4.Clamp
Fig.4-2-13
2) Connect negative cable to battery.
3) After installation, start engine and check it
for leaks.
Fuel Tank
[Removal]
1) Disconnect negative cable from battery.
2) Disconnect fuel level gauge lead wire.
3) To release the pressure in fuel tank, remove
fuel filler cap and then, reinstall it.
4) Raise car on hoist.
5) Drain fuel by removing drain plug.
6) Remove filler hose protector.
7) Disconnect filler hose from fuel tank.
.8) Disconnect fuel hosesand pipe from fuel tank.
9) Remove fuel tank.
4-34

[Fuel tank purging procedure]
WARNING:
This purging procedure will NOT remove
all fuel vapor. Do not attempt any repair
on tank where heat or flame is required, as
an explosion resulting in personal injury
cou Id occur.J
The following procedure is used for purging the
fuel tank.
1) After removing fuel tank, remove all hoses,
fuel level gauge from fuel tank.
2) Drain all remaining fuel from tank.
3) Move tank to flushing area.
4) Fill tank with warm water or tap water, and
agitate vigorously and drain. Repeat this
washing until inside of tank is clean.
Replace tank if inside is rusty.
5) Completely flush out remaining water after
washing.
[ Installation]
Reverse removal procedure for installation using
care for the following.
Tightening torque30-45 Nm
for fuel tank(3.0- 4.5 kg-m)
drain plug(22.0 - 32.5 lb-ft)
Refer to Fig. 4-2-5 for piping and clamp posi-
tions.
l Make sure for correct hose-to-pipe connec-
tion.
l Clamp hoses securely.
l Upon completion of installation, start engine
and check hose joints for leaks.
MAINTENANCE SERVICES
Fuel Lines
Visually inspect fuel lines and connections for
evidence of fuel leakage, hose cracking, and
damage. Make sure all clamps are secure.
Repair leaky joints, if any.
Replace hoses that are suspected of being crack-
ed.
Fig. 4-2-14
Fuel Filler (tank) Cap
Visually inspect gasket of fuel filler cap.
If it is damaged or deteriorated, replace filler cap
with new one.
NOTE:
If cap requires replacement, only a cap with
the same features should be used. Failure to
use correct cap can result in a serious malfunc-
tion of the system.
Fig. 4-2-15
1. Fuel filler cap
2. Fuel filler capgasket
Fuel Filter
As said before, this filter does not permit dis-
assembly: it is to be replaced with a new one
periodically.
Replace fuel filter referring to previous item of
“Fuel Filter Removal and Installation”.
This servicing must be performed in a well
ventilated area and away from any open
flames (such as gas hot water heaters).
4-35

DECELERATION MIXTURE CONTROL SYSTEM
This system consists of a MCV (Mixture Control Valve), jet and vacuum hoses.
This system is designed to introduce fresh air into the intake manifold to reduce generation of excessive
HC and CO emission caused by temporary rich air-fuel ratio while rapid deceleration.
The MCV has a pressure balancing orifice and check valve on its diaphragm, and closes when manifold
vacuum is constant. As manifold vacuum increases according to rapid deceleration, manifold vacuum
applies to MCV chamber “B” through jet, the MCV opens and introduces fresh air into the intake mani-
fold. When manifold vacuum becomes constant, pressure difference between two sectioned chambers “A”
and “B” gradually diminishes through pressure balancing orifice, then the MCV closes.
1.Carburetor7. Valve
2. Intake manifold8. Filter3.MCV9. Jet (Colorless)
4.Chamber “A”9-1. Gray side
5.Orifice10. Diaphragm
8.Chamber “B”11. Check valve
Fresh airc=l
1Vacuum
Fig. 5-l-7Deceleration mixture control system
5-9

NOTE:
l To check therm0 sensor for operation at
higher than 40°C (104” F) temperature when
therm0 sensor is lower than 25°C (77” F),
remove therm0 sensor from air cleaner cap
and warm it up with hair drier or photo light
before checking.
l Never touch bimetal or valve in therm0
sensor.
1. Therm0 sensor
2. Nozzle3. Nozzle
4. Air cleaner cap
Fig. 5-3-6 Checking therm0 sensor
5) After checking, reinstall air cleaner case cap,
and connect 2 vacuum hoses to therm0
sensor.
[Check valve]
1) Remove check valve with vacuum hose.
2) Using vacuum pump gauge, check for the
following.
When pump operation is stopped,pump gauge pointer stays constant.
When pump is operated, pointermoves considerably but movesback to zero position as soonas pump operation is stopped.
Fig. 5-3-7 Checking check valve
If found defective, replace.

3) Install check valve with its orange side directed
toward therm0 valve.
EVAPORATIVE EMISSION CONTROL
SYSTEM
Checking vapor storage canister
DO NOT SUCK the nozzles on canister
1) Disconnect negative cable at battery.
2) Disconnect 3 hoses from canister.
3) Remove canister.
air into pipe A strongly, and air should come
out from pipe B.
pass through pipe A, C or D.
6) When air is blown into pipe C, air should
come out from pipe A, B and D.
If operation differs from above description,
canister must be replaced.
1. Vapor to carburetor6. Air flow under
2. Vapor from fuel tankvacuum condition
3. Filter7. Vapor from float
4. Charcoalchamber when ignition
5. Filterswitch is “OFF”
Fig. 5-3-8 Checking canister
7) Install canister and connect hoses and battery
negative cable.
5-20