1987 MAZDA 626 Workshop Manual

4D SUPERCHARGING SYSTEM (RF-CX)
SUPERCHARGING SYSTEM (RF-CX)
TROUBLESHOOTING GUIDE

Engine
hard
starting

Poor

acceleration

Excessive

blue
smoke

Excessive

black
smoke

Excessive

compressed
air
temperature
(Buzzser
sounds)

Excessive

noise
Possible Cause Remedy (reference page)
*
*
Comprex supercharger Rotor stuck Casing damaged Rotor bearing damaged
Replace (4D—14)
* * * Drive system
of
Comprex supercharger Drive belt loose
or
worn Repair
or

replace
(4D-12) * Idler pulley damaged
Repair
or

replace
(4D-12) * Pulley bolt loose
or
worn
Repair
or

replace
(4D-12)
* Wastegate
Valve
not
open Clean
or
repace (4D-12) ik * Valve
not
closed
Clean
or
repace (4D-12)
* * Starting valve
Valve
not
open Repair
or
replace (4D-15)
* * Valve
not
closed
Repair
or
replace (4D-15) * Bypass valve
not
open
Repair
or
replace (4D-15)
* * Bypass valve
not
closed
Repair
or
replace (4D-15)
* Intercooler dirty Clean
or
replace (4D-16)
* * * * Intake
air
system Fresh
air
side clogged (Air cleaner
ele-
ment,
etc.)

Repair
or
replace * Compressed
air
side clogged (Intercool-
er,
etc.)
Repair
or
replace
* Fresh
air
side leaks
Repair
or
replace
* * * Compressed
air
side leaks
Repair
or
replace
* Exhaust system
Exhaust
gas
breaked Repair
* * * * * Exhaust pipe clogged
Repair
* Silencer damaged
(in
fender,
in air
clean-er,
in air
funnel, Comprex insulator) Repair
or
replace
* Bolt
and nut
loosend Repair
76G04D-022
4D—10

4D SUPERCHARGING SYSTEM (RF-CX)
ON-VEHICLE INSPECTION
Boost Pressure
1. Connect a pressure gauge to the hose from the
intake manifold.
2. (On chassis dynomometer, full load)
(1) Set the vehicle on a chassis dynomometer.
(2) Run the vehicle in gear at 3,000 rpm with the
acceleration pedal fully depressed.
(3) Measure the boost pressure.
Boost pressure:
82 kPa (0.87 kg/cm2, 8.1 psi)
Note
The above inspection should be done on a
chassis dynomometer. If a dynomometer is
not available follow the below procedure.
3. (Off chassis dynomometer, no load)
(1) Shift the transaxle out off gear.
(2) Run the engine in neutral at 3,000 rpm of the
engine no load.
Measure the boost pressure.
Boost pressure:
5 kPa (0.05 kg/cm2, 0.7 psi)
Note
The boost pressure is varied by engine speed
and engine load.
(3) Remove the starting valve bypass hose.
(4) Check that the bypass valve is closed at 3,000
rpm.
4.
If
the pressure is below specification, check the fol-
lowing. Replace the Comprex supercharger if
necessary.
(1) Intake air and exhaust passages leakage
(2) Intake air and exhaust passages clogged
(3) Wastegate (Refer to 4D—12.)
(4) Starting valve (Refer to 4D—15.)
(5) Fuel system (Injection nozzle... refer to page
4D—31, injection pump...refer to page 4D—24,
etc.)
5. If the pressure exceeds specification, check the
wastegate operation. (Refer to page 4D—12.)
4D—11

4D SUPERCHARGING SYSTEM (RF-CX)
Starting Valve
1. Remove the bypass hose from the starting valve.
2. Check that the bypass valve in the starting valve
opens and closes repeatedly at idle.
3. Check that the bypass valve is closed when the
accelerator pedal is fully depressed when the en-
gine speed is more than 3,000 rpm.
4. If necessary replace the starting valve.
76G04D-026
Comprex Supercharger Drive Belt
1. Check the drive belt for wear, cracks, or fraying.
2. Check the drive belt deflection by applying moder-
ate pressure (98 N, 10 kg, 22 lb) midway between
the pulleys.
3. If necessary, loosen the bolt and adjust the belt
deflection by turning the adjusting bolt.
New : 4.0—5.0 mm (0.16—0.20 in)
Used: 4.5—5.5 mm (0.18—0.22 in)
Tightening torque:
16—23 Nm (1.6—2.3 m-kg, 12—17 ft-lb)
Wastegate
1. Disconnect the boost air hose from wastegate to
the intake manifold, and apply compressed air.
76G04D-028
2. Check that the wastegate actuator pulls the rod at
the specified pressure.
Pressure: 137 kPa (1.4 kg/cm2, 20 psi)
Caution
Do not apply more than 196 kPa (2.0 kg/cm2,
28 psi) pressure.
76G04D-087
4D—12

SUPERCHARGING SYSTEM (RF-CX) 4D
COMPREX SUPERCHARGER
Removal and Installation
1. Remove in the sequence shown in the figure.
2. Install in the reverse order of removal.
3. Check for air/exhaust leakage.
8—11 N m ''"'^'gs , (80—110 cm-kg, 69—95 In-lb)
8—11 N-m (80—110 cm-kg, 69—95 In-lb)
IsSJ 19-26 N-m (1.9—2.6 m-kg, 14—19 ft-lb)
34—49 N m (3.5—5.0 m-kg, 25—36 ft-lb)
22—26 N-m (2.2—2.7 m-kg, 16—20 ft-lb)
76G04D-029
1. Air hose
2. Air funnel assembly
3. Exhaust pipe
4. Supercharger insulator
5. Exhaust manihold stay
6. Drive belt
7. Exhaust joint pipe
8. Idle pulley
9. Comprex supercharger
Caution
a) Be careful not to bend the rod or bracket
of the wastegate.
b) Cover the intake and exhaust ports to pre-
vent dirt or other material from entering.
76G04D-030
4D—13

4D SUPERCHARGING SYSTEM (RF-CX)
Inspection
Air casing, exhaust casing, rotor housing
Check the air casing, exhaust casing, and rotor hous-
ing for cracks or damage. Replace the Comprex su-
percharger if necessary.
76G04D-031
Rotor and rotor bearing
Check that the rotor turns smoothly. Replace the Com-
prex supercharger if necessary.
76G04D-032
L sSRs^w^
j^r^SllfeJN
I^glji
H/yxA
Air funnel
Check the air funnel and insulator for cracks or
damaged. Replace if necessary.
76G04D-033
4D—14

SUPERCHARGING SYSTEM (RF-CX) 4D
STARTING VALVE
Removal and Installation
1. Remove in the sequence shown in the figure.
2. Install in the reverse order of removal.
3. Check for air leakage.
76G04D-036
1. Air hose
2. Vacuum pipe
3. Starting valve
Note
Resistance will be felt because of the magnet
when opening the valve.
76G04D-034
Inspeciton
Bypass valve
Check that the bypass valve opens smoothly.
Replace the starting valve if necessary.
Starting valve
Check that the starting valve opens smoothly.
Replace the starting valve if necessary.
4D-15

4D SUPERCHARGING SYSTEM (RF-CX)
INTERCOOLER
Removal and Installation
1. Remove in the sequence shown in the figure.
2. Install in the reverse order of removal.
3. Check for air leakage.
76G04D-037
5. Front bumper (Refer to Section 14.)
6. Cooling fan
7. Air pipe
8. Intercooler
Inspection
Check the intercooler for cracks or damage. Replace
if necessary.
8—11 N-m (80—110 cm-kg, 69—95 In-lb)
1. Battery
2. Battery carrier
3. Front grille (Refer to Section 14.)
4. Headlight (Refer to Section 14.)
76G04D-038
4D—16

4D SUPERCHARGING SYSTEM (RF-CX)
BOOST AIR TEMPERATURE SENSOR
Removal
Remove the boost air temperature sensor from the
compressed air funnel.
76G04D-039
Thermometer
Inspection
1. Place the boost air temperature sensor in oil.
2. Heat the oil and check continuity of the sensor with
an ohmmeter. Replace if necessary.
Continuity : over 150°C (302°F)
No continuity: below 143°C (289°F)
76G04D-040
Installation
Install the boost air temperature sensor in the com-
pressed air funnel.
Tightening torque:
29—39 N m (3.0—4.0 m-kg, 22—29 ft-lb)
76G04D-041
4D—17