1990 MAZDA 232 clutch

i
1
INDEX H
I. Clutch pedal (BP DOHC Turbo)
Removal I inspection /
Installation ................................ page H-l 1
2. Crutch master cylinder (BP DUHC Turbo)
Overhaul .....................................
page H-l 5
3. Clutch cover
Removal I Installation.. ................
page H-t 9 4. Clutch disc
Removal I Installation..
................ page H-19
5. Pilot bearing
Removal J Installation ..................
page H-l 9
6. Flywheel
Removal I installation.. ................ page H-l 9
H-3

H OUTLINE
OUTLINE
OUTLINE OF CONSTRUCTION
A hydraulic clutch control mechanism is used.
The basic construction is the same as that of 323 2WD model, but there is no interchangeability of parts
except for the release cylinder.
1. An assist/return spring is used on the BP DOHC Turbo model to reduce the required clutch pedal effort..
2. The hydraulic clutch master cylinder for the 8P DOl-lC Turbo model has a built-in check valve.
3. To improve clutch operation feeling and increased parts life, a friction plate and needle roller bearings
are used between the release fork and the release bearing.
93GOHX-704
SPECIFICATIONS
Hem
Clutch control Engine/Transaxle
BP SUHC BP DOHC Turbo
GSMX-R
Hydrautic
Clutch cover
Type
Set load
N (kg, lb) Diaphragm spring
3,846 (392, 862) 5,494 (560, I ,232)
Outer diameter 1
mm (in) 225 (8.858) 230 (9.055)
I 1 nner diameter mm (in)
I 150 (5.906)
I 155 (6.102) I
CI utch disc
Pressure plate side
mm {in) 4.1 (0.161) 3.2 (0.126)
Thickness f
Flywheel side
mm (in) 3.5 (0.138) 3.2 (0. f 26)
I Type I Suspended
I
Clutch pedal LHD 6.55 Pedal
ratio
RHD 6.7
Full stroke mm (in)
I 135 (5.32)
I
Height (With carpet) mm [in)
I I 96-204 (7.72-8.03)
I
Master cylinder Inner diameter
mm {in)
I 15.87 (0.625)
Release cylinder inner diameter
mm (in)
I - 19.05 (0.750)
I
Clutch fluid SAE J1703 or FMVSSI 16 DOT-3
93GOHX-705
H-4

CLUTCH CONTROL H,
CXUTCH CONTROL
CLUTCH PEDAL
l An assistireturn spring is used on BP DO-K Turbo engine-equipped models to reduce the required pedal
effort.
l The assist/return spring is mounted vertical to the pedal for a compact arrangement.
wiNGi B G”3 * RANGE A
RANGE B + + RANGE A
Operation With the clutch pedal fully
released, the assist/return spring is compressed, causing force F to act upon ful-
crum 0,
As a result, force Fy is created, and acts upon fulcrum @ to hold the pedal outward.
1 1 When clutch pedal depressed.
(1) Fukrum @ within range A
When the pedal is depressed, it moves inward, centered upon fulcrum @.
Fy, which is the force opposing pedal movement, acts upon futcrum @ until fulcrum @ crosses the
imaginary line connecting fulcrums
@ and @
As a result, there is a slight feeling of resistance when the clutch pedal is first depressed.
(2) With fulcrum @ within range 8
When fulcrum @ crosses the imaginary line between fulcrums @ and @, Fy now acts in the same
direction as pedal
movement, thus reducing the force required to depress the pedat.
H-5

H CLUTCH CONTROL
RANGE B CT] e RANGE A
RANGE B ++I + RANGE A
93GOHX-70
2. When clutch pedal released.
(1) With fulcrum @ within range B
When the clutch pedal is released, reaction force f (from clutch master cylinder push rod) is applied,
and fy force pushing outward overcomes Fy force, with the result that the clutch pedal moves out-
ward, centered upon fulcrum @.
(2) With fulcrum @ within range A
When futcrum @ crosses the imaginary iine 4etween fulcrums @ and a, force Fy, which is a result
of force F trying to expand the spring, is added to fy and pushes the pedal fully outward.
t-l-6

C1UTCl-i CONTROL H
CLUTCH MASTER CYLINDER
‘CHECK VALVE
RHD
CHECK VALVE
93GOHX-708 A hydraulic clutch master cylinder with a built-in check valve is used on the BP DOHC Turbo model.
This is to provide smooth engagement of the clutch disc by controlling (by the check valve) the flow of fluid
from the clutch release cylinder back to the master cylinder when the clutch pedal is released, thus cushion- ing the impact “shock”.
l-l-7

H CLUTCH CONTROL
RELEASE BEARING
ROLLER BEARING
CLUTCH PEDAL RELEASED
RELEASE FORK RELEASE E?EARfNG
CLUTCH PEDAL DEPRESSED To improve clutch operation feeling and increased parts life, a newly designed friction plate and needle roller
bearings are used between the release fork and the release bearing.
With
the kdusion of this friction plate, the force required to depress the clutch pedal is reduced because
the usual sliding-contact action between the release bearing and the release fork is changed to a rolling
action of the friction plate,
H-8

SUPPLEMENTAL SERVICE INFORMATION, TROU8LESHOOTlNG GUIDE H
SUPPLEMENTALSERVICE INFORMATION
The following points in this section are changed in comparison with 323 Workshop Manual (1206IO-89F).
Troubleshooting guide
Clutch fluid (with ABS)
l Replacement
Clutch pedal (BP DOHC Turbo) Clutch release cylinder (with ABS) l Air bleeding
Clutch unit
l Removal I Inspection I installation
Clutch master cylinder
(BP DOW Turbo or with ABS) l Removal I Inspection I installation
93GOHX-710
l Removal I Inspection I Installation (BP DUHC Turbo)
l Air bleeding (with ABS)
l Overhaul (BP DUHC Turbo)
TROUBLESHOOTING GUlDE
Problem
Possibte Cause Remedy Page
Slipping
Clutch disc facing worn excessively
Replace U-l 9
Clutch disc facing surface hardened or oifed
Repair or replace H-l 9
Pressure plate damaged Replace H-19
Diaphragm spring damaged or weakened
Replace H-l 9
Insufficient clutch pedal piay
Adjust H-12
Clutch pedal sticking
Repair or replace U-11
Flywheel damaged
Repair or replace H-19
Faulty
Excessive runout or damaged clutch disc
Replace H-19
disengagement
Clutch disc spiines rusted or worn ’
Remove rust or replace H-l 9
Clutch disc facing oiled
Repair or replace H-19
Diaphragm spring weakened
Reptace H-19
Excessive clutch pedal ptay
Adjust -
Insufficient clutch fluid
Add fluid H-10
Leakage of clutch fluid
Locate and repair or -
replace
Clutch vibrates
Clutch disc facing oiled
Repair or replace H-l 9
when accelerating
Torsion rubbers weakened
u-19 Clutch disc facing hardened or damaged Replace
Repair or replace H-19
Clutch disc facing rivets loose
Replace H-l 9
Pressure plate damaged or excessive runout
Replace H-l 9
Flywheel surface hardened or damaged
Repair or replace H-19
Loose or worn engine mount
Tighten or replace -
Clutch pedal
sticking Pedal shaft not properly lubricated
Lubricate or replace H-l 1
Asistireturn spring damaged or poor adjust
Replace or adjust H-11, 12
Abnormal noise
Clutch release bearing damaged
Replace N-1 9
Poor iubrication of release bearing sleeve
Torsion rubbers weakened Lubricate or replace H-19
Replace u-t9 Excessive crankshaft
end play
Repalr -
Pilot bearing worn or damaged
Replace H-79
Worn pivot points of reiease fork
Repair or replace H-19

H CLUTCH FLUID (WITH ABS)
CLUTCH FLUID (WITH ABS)
PREPARATION
SST
49 0259 770B
For
Wrench, flare nut
m air
bleeding
1
93GOHX-714 93GOHX-712
REPLACEMENT
Note
l A common reservoir is used for the clutch and brake
system fluids.
l The fIuid in the reservoir must be maintained at 314
tevet or higher during replacement.
Caution
l Be careful not to spill the fluid on a painted surface.
If this should happen, wash it off immediately.
l Do not mix different brands of fluid.
l Do not reuse the clutch fluid that was drained.
1. Drain the brake fluid from the master cylinder by pumping
it through a wheel cylinder bleed screw.
2. Remove the bleeder cap from the clutch release cylinder
and attach a vinyl hose to the bleeder plug.
93GOHX-77 3
3. Place the other end of the vinyl hose in a clear container.
4. Fill the reservoir with new fluid to the MAX mark.
5. Slowly pump the clutch pedal several times.
6. With the clutch pedal depressed, loosen the bleeder screw
with the SST to let the fluid escape. Close the bleeder screw
with the SST.
7. Repeat Steps 4 and 5 until only clean fluid is seen.
8. Tighten the bleeder screw.
Tightening torque:
5.9-8.8 Nom (60-90 cm-kg, 52-78 in-lb)
9. Add fluid to the MAX mark.
IO. Slowly pump the clutch pedal several times.
Verify that there is no fluid leakage.
11.
Check operation of the clutch system.
12. Bleed and check operation of the brake system.
(Refer to Section PJ