Infiniti M45 (Y34). Manual - part 260

BRAKE MASTER CYLINDER

BR-19

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3.

Insert the plate and the guide assembly into the cylinder body.

CAUTION:

●

Be careful not to damage the rod of the primary piston. 

●

Pay attention to the orientation of the guide assembly.

●

Do not drop the O-ring. 

4.

Be careful not to damage the rod of the primary piston covering
it with cloth. Then insert snap ring into cylinder with pushing pri-
mary piston. 

CAUTION:

●

Be careful to check the snap ring in the inner tip of the
cylinder body. 

●

Do not reuse the snap ring.

5.

Align the slit in the center of the piston with the axial direction of
the valve stopper to assemble. Visually check the secondary
piston slit from the valve stopper mounting hole, and install the
valve stopper.

CAUTION:

Always replace the O-ring of piston pin with new one in the
repair kit.

6.

Apply brake fluid to a grommet, and press it into the master cyl-
inder to install.

CAUTION:

Do not reuse the grommet.

7.

Press a new reservoir tank in the cylinder body.

SFIA1469E

BRA0561D

SFIA0997E

BR-20

BRAKE BOOSTER

BRAKE BOOSTER

PFP:47200

On-Vehicle Service

AFS000K7

OPERATING CHECK

With the engine stopped, change the vacuum to the atmospheric
pressure by depressing the brake pedal several times. Then with
brake pedal fully depressed, start the engine and when the vacuum
pressure reaches the standard, check that the clearance between
the brake pedal and floor panel decreases.

CAUTION:

Depressing pedal interval is approximately 5 seconds.

AIRTIGHT CHECK

●

Run the engine at idle for approximately 1 minute, and stop it
after applying vacuum to the booster. Depress the brake pedal
normally to change the vacuum to the atmospheric pressure.
Check that distance between the brake pedal and floor panel
gradually increases.

CAUTION:

Depressing pedal interval is approximately 5 seconds.

Removal and Installation 

AFS000K8

REMOVAL

CAUTION:

●

Be careful not to splash brake fluid on painted areas; it may cause paint damage. If brake fluid is
splashed on painted areas, wash it away with water immediately.

●

Be careful not to deform or bend brake pipes, during removal of booster.

1.

Remove the vacuum hose from the brake booster.

2.

Remove the master cylinder. Refer to 

BR-13, "Removal and Installation"

 .

3.

Remove the snap pin and clevis pin on the clevis in the passenger compartment, and remove the input
rod from the brake pedal.

4.

Remove the mounting nuts on the pedal bracket.

5.

Remove the booster assembly from the engine room.

BRA0037D

SBR365AA

SFIA2235E

BRAKE BOOSTER

BR-21

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INSPECTION AFTER REMOVAL
Output Rod Length Inspection

1.

Using a handy vacuum pump, apply a vacuuming of –66.7 kPa
(–500 mmHg,19.69 inHg) to the brake booster.

2.

Check output rod length.

INSTALLATION

1.

Loosen the lock nut to adjust the input rod length so that the
length “B” (in the figure) satisfies the specified value.

2.

After adjusting 

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, temporarily tighten the lock nut to install the

booster assembly to the vehicle. At this time, make sure to
install a gasket between the booster assembly and the vehicle.

3.

Connect the brake pedal with the clevis of the input rod.

4.

Install the pedal bracket mounting nuts and tighten them to the
specified torque.

5.

Install the master cylinder to the booster assembly. Refer to 

BR-

13, "Removal and Installation"

 .

6.

Adjust the height and play of the brake pedal.

7.

Tighten the lock nut of the input rod to the specified torque.

8.

Bleed air. Refer to 

BR-9, "Bleeding Brake System"

 .

Standard dimension when vacuum
 –66.7 kPa (–500 mmHg, –19.69 inHg):

                      With VDC:

– 6.2 mm (– 0.24 in)

                     With ACC:

 10.4 mm (0.409 in)

SBR208E

Length “B”

: 125 mm (4.92 in)

SGIA0060E

BR-22

VACUUM LINES

VACUUM LINES

PFP:41920

Removal and Installation

AFS0029Q

CAUTION:

●

Because vacuum hose contains a check valve, it must be installed in the correct direction. Refer to
the stamp or label to confirm correct installation. The brake booster will not operate normally if
hose is installed in the wrong direction.

●

Insert vacuum hose for at least 24 mm (0.94 in).

●

Do not use lubricating oil during assembly.

Inspection

AFS0029R

VISUAL INSPECTION

Check for improper assembly, damage and deterioration.

CHECK VALVE INSPECTION
Airtightness Inspection

Use a handy vacuum pump to check.

1.

Vacuum hose

2.

Clamp

SFIA2236E

SBR225B

When connected to booster side (1):

 Vacuum decrease should be within 1.3 kPa 
(10 mmHg, 0.39 inHg) for 15 seconds under 
a vacuum of – 66.7 kPa (– 500 mmHg, – 
19.69 inHg)

When connected to engine side (2):

 No vacuum will be applied

SFIA0210E