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46
BRAKES
Use always a wooden mallet to tap Seal into
the Rear housing.
4.
Apply grease on the Seal.
5.
Push Operating rod assembly in theValve body
and assemble Key. Place Key retainer over Key
and press it.
6.
Place and position the Diaphragm, Diaphragm
disc and Valve body assembly on the Rear
housing.
7.
Place Diaphragm over Rear housing groove.
8.
Place the Rear housing assembly with valve
body and operating rod assembly with Key on
locking fixture.
9.
Place Rubber reaction disc, Push rod, Spring
seat and Spring.
10. Place and Front housing on the Spring and
match its notches with Rear housing notches.
11. Tighten the fixture handle simultaneously
aligning the notches of Front housing and Rear
housing notches in line. Continue tightening to
allow the Front housing notch groove matches
with rear housing.
12. Rotate the rods uniformly without jerk to avoid
twisting of Diaphragm and lock the housings
and match the marking.
13. Avoid grease / Oil contact with diaphragm
during assembly.
14. Loosen the handle and remove the unit from
the fixture.
15. Assemble the Grommet and Non return valve
in Front housing.
16. Assembly the Filters, Retainer and Gaiter.
Ensure Gaiter is located properly on Rear
housing groove.
17. Assemble Nut on Operating rod assembly and
assemble Fork on Operating rod assembly.
Ensure that booster input rod standout dim is
111 + 0.5 mm Fig. 53
18. Place Sealing ring , Spacer on Front housing and
tighten Nuts.
19. Mount the unit on the vehicle and connect brake
pedal return spring. Adjust pedal position and free
play. Install the eccentric pin (smear pin with
molycoat grease)
20. Connect the vacuum pump line with the Non
return valve of vacuum brake valve.
21. Mount the Master cylinder on the vacuum
brake valve and connect the hydraulic lines.
TEST PROCEDURE
1.
Bleed the hydraulic lines. Ref. brake bleeding
procedure.
2.
Apply / release the brake without vacuum
assistance and check for free return if brake
pedal.
3.
Depress the brake pedal fully before starting the
engine (i.e. without vacuum in the system). Start
the engine. As vacuum builds up in the system,
the brake pedal becomes light indicating proper
function of the brake valve and the brake system.
4.
Check for vacuum leak in brakes on/off positions
by observing the vacuum gauge.
5.
Apply / Release the brake with vacuum and
check for free return of brake pedal.