Background: In applications fitted with Vacuum Power Assist, Non Release or the inability to select gears can be experienced in some cases. Where this occurs, CI recommends investigation of the Actuation System as the first step in trouble shooting. After fitment of the new clutch assembly to the machined flywheel in accordance with Manufacturers recommendations we recommend applying the following 3 step process:
A. Clutch Bleeding:
Most models have a coiled or spiral type line to the flexible hose. This coiled line can make bleeding of the hydraulics difficult. Some installers have found that replacing the coiled line with a genuine Nissan flexible line to the slave cylinder (part # 30855-01J10) decreases the chance of trapped air after bleeding.
. Insure bleeding procedure is completed and the line is free of air.
B. Vacuum Booster adjustment:
A worn vacuum booster diaphragm can be the cause of faulty booster operation. Investigate the condition of the diaphragm and replace (suggested replacement – Nissan part # 30684-01J25 found in Nissan parts section 470) if required.
The booster is adjustable at the output rod of the booster (Ref Fig #1) and between the booster and the Master Cylinder (Ref Fig #2). After the booster is rebuilt, ensure that the adjustment of the push rod into the master cylinder is correct. Correct adjustment should be 1.30 – 1.55mm below the surface of the alloy mounting adaptor. If a non genuine master cylinder is used, back off the push rod and place bearing blue on the pushrod end, bolt up the master, and then remove. Repeat until the pushrod is barely touching the piston of the master cylinder.
The clutch pedal is adjustable for height. The pedal height should be from floor to face of pedal. Please correct for model specification – Pedal Height “H” Measured from floor panel to pedal pad.
Wagon – RD28ETi & TD42 – 195 – 205 mm Wagon – TB42, TB45E, TB48DE & ZD30 – 200 – 210 mm Cab Chassis – TD42 – 185 – 195 mm Cab Chassis – ZD30 – 200 – 210 mm
3. Adjust the pushrod (Fig 2.) 1 to 3 mm on the booster to correctly set any pedal free play.
C. Pivot Ball / Throw-out arm
These vehicles can cover high kilometres in difficult conditions. This creates the potential for significant wear in both the pivot ball and the socket in the throw-out arm.
This wear may be disguised by dirt or grime. Clean the mechanism and inspect both the pivot ball and the socket in the throw-out arm for wear.
Restore the pivot point to the correct position as necessary.
Conclusion:
In many cases Non Release or the inability to select gears can be an actuation fault rather than a clutch Kit fault. We recommend the 3 step trouble shooting process be applied to ensure correct function of the clutch kit.
