Saab SONETT III Service Manual page 98

OVERHAUL OF MASTER CYLINDER
The master cylinder should only be dismantled if there
is no exchange system for this unit.
Dismantling
1. Remove the rubber bellows 11 together with retaining
plate 8 and the push rod 31.
2. Press down the spring retainer 30 and rem ove the spiral
clip 29 with the aid of a small screwdriver.
3. Remove the outer lock ring 28, the nylon bearing 27,
the cup 26, and the washer 25.
4. Remove the inner lock ring 24 with the aid of special
tool 784199 and remove the pistons.
Inspection
1. Check that the cylinder bore is not scored.
2. Check that the bypass holes are clean by probing with
a piece of thin steel wire.
3. Check all parts, and renew any defective ones.
Interna' rubber parts should be replaced by new ones,
which are available in suitable kits.
Cleaning
Always use spirit for cleaning the cylinder parts.
Reassembly
Before reassembling the master cylinder, dip all parts in
brake fluid.
1. Locate the cups on the pistons and check that they
are correctly positioned, see fig.
1-
REMOVING THE LOCK RING 13
14
S383
Tool 784199
NOTE
Be carefull when removing the locking ring and the
washer so that the surface of the pistons not be
damaged.
5. Compress the intermediate spring 18 together with
spring holder 20 and drive out the retaining pin 19,
using a suitable pin punch. This will separate the two
pistons 10 and 14, and allows the withdrawal of the
spring 18 and spring holder 20.
6. Withdraw the non-return valves. Take care not to
distort the spring clip 44 when removing it from the
valve body.
7. Remove the six bolts retaining the cover of the brake-
fluid reservoir 5 and
take off the cover together with
the gasket.
FITTING THE PISTON WASHER
12. Primary cup
13. Piston washer (dished)
14. Secondary piston
2. Install the spring 18 on the pistons and press them
together so that the retaining pin 19 can be installed.
3. Fit the pistons in the cylinder. Note! Be carefull so
that the gaskets not be damaged.
4.
Install the piston stop 23.
5. Mount spiral clip 24 with the aid of tool 784199.
6. Install the washer 25, the secondary cup 26 and
the nylon bearing 27. Lock with spiral clip 28.
7. Install spring 9 and spring retainer 30 on the pri-
mary piston 10.
8.
Com press the retain spring 10 and install the spiral
clip 29.
9.
Lubricate the small end of the push-rod 31 with
silicon grease and install the rubber bellows 11 with
retainer 8.
10. Screw on the outlet adapters and non returnvalves.
Tighten to 38 Nm (28 ft.lb ., 3.8 kpm).
11. Install the cover 5 and tighten the screws to 7 Nnn
(6
ft.lb ., 0.7 kpm).
521-3
SAAB
Nov. 1972