Clutch with manual transmission - dry, single plate, diaphragm

The clutch mechanism is located in the crankcase, combined with the gearbox.

Nissan Almera clutch design Nissan Almera clutch design

The clutch basket is connected with six bolts to the engine flywheel.

Three pins are pressed into the flywheel to center the basket.

The clutch housing contains a diaphragm spring made of spring steel.

The diaphragm spring consists of eighteen petals, which are elastic release levers.

Due to the elasticity of the levers, the diaphragm spring creates a uniform pressure on the clutch pressure plate and contributes to smooth engagement and disengagement of the clutch.

The need to replace the basket occurs when the diaphragm spring petals are worn to a depth of more than 0.8 mm, as well as in the event of a decrease in pedal force when the clutch is disengaged, which indicates a large wear of the pressure plate surface or a diaphragm spring settlement.

Nissan Almera clutch design

The driven plate with a spring damper is mounted on the splines of the input shaft of the gearbox between the flywheel and the pressure plate.

The damper provides an elastic connection between the clutch disc and the input shaft of the gearbox, and also dampens torsional vibrations arising from dynamic loads in the transmission and uneven engine operation, two friction linings of the disc are riveted on both sides to the spring plate, which, in turn, turn, riveted to one of the two damper plates.

A disk hub is installed between the damper plates.

Damper springs are installed in the holes of the hub and damper plates.

The damper plates are connected by three support pins.

In the disc hub, opposite the support pins, there are cutouts that allow the hub to rotate within certain limits relative to the damper plates, while compressing the damper springs.

This allows you to reduce dynamic loads in the transmission when starting the car and when shifting gears.

The driven disk is replaced if its axial runout in the area of ​​the friction linings is more than 0.5 mm, oiling, cracking, scuffing or uneven wear of the linings, weakening of the rivet joints, and also if the heads of the rivets are deepened from the surface of the linings by less than 0.2 mm.

Nissan Almera clutch design

Clutch drive on cars - cable, backlash-free.

The front end of the cable is attached to the clutch release fork, and the rear end is attached to the clutch pedal holder.

The front tip is threaded, used to adjust the clutch release drive.

The clutch pedal is mounted on an axle in the pedal assembly bracket. A pedal return spring is installed on the same axle.

The fork pivots on a ball joint installed in the clutch housing.

A clutch release bearing is installed between the clutch release fork and the diaphragm spring petals.

There are two hooks on the bearing sleeve, with which it is hooked onto the legs of the fork. A clutch drive scheme has been applied, in which the bearing is constantly pressed against the petals of the diaphragm spring.

The bearing moves freely along the guide sleeve pressed into the clutch housing.

Clutch disengagement is as follows.

When the clutch pedal is depressed, the cable turns the clutch release fork, which moves the bearing along the guide sleeve.

The bearing presses on the petals of the diaphragm spring.

The spring, deforming, stops pressing the pressure plate against the flywheel, while the pressure plate moves away from the flywheel, as a result of which the engine crankshaft and the gearbox input shaft can rotate independently of each other.

When the clutch pedal is released, the bearing returns to its original position, while the diaphragm spring again begins to press on the pressure plate, which, in turn, presses the driven disc against the flywheel - as a result, the transmission of torque resumes.

Possible clutch failures and solutions

- Causes of malfunction

Troubleshooting

Jerks when pulling away:

- Clutch cable jamming

On carry engine oil on the cable. If the cable is damaged, replace it

- Jamming of the hub of the driven disk on the splines of the input shaft of the gearbox

Clean the splines from dirt, remove minor damage with a needle file.

In case of significant wear or damage to the splines, replace the disc or the input shaft of the gearbox.

Before assembling, apply SHRUS-4 grease to the splines.

- Deformation of the driven disk

Replace driven disc

- Loose fastening of the friction linings of the driven disk, severe wear or cracks on the linings

Replace driven disc

- Loss of elasticity of the spring plates of the driven disk

Replace driven disc

- Significant settlement or breakage of the springs of the damper of torsional vibrations, wear of the windows under the springs

Replace driven disc

- Seizures on the working surfaces of the flywheel or pressure plate

Replace flywheel or clutch cover with pressure plate assembly (clutch basket)

- Oiling the working surfaces of the friction linings of the driven disk

Rinse oily surfaces thoroughly with mineral spirits or gasoline and wipe them dry. Replace heavily oiled driven disc. Eliminate the cause of oiling.

Rattle, knock or noise when engaging the clutch:

- Significant settlement or breakage of the springs of the damper of torsional vibrations, wear of the windows under the springs

Replace driven disc

- Deformation of the driven disk

Replace driven disc

- Loose fastening of the friction linings of the driven disk, severe wear or cracks on the linings

Replace driven disc

Increased noise when disengaging the clutch:

- Wear, damage or leakage of grease from the clutch release bearing

Replace bearing

Clutch slips (not fully engaged) when the gas pedal is pressed hard, the engine picks up speed, but the car does not accelerate:

- Lubrication of the flywheel, pressure plate and friction linings of the clutch disc

Rinse oiled surfaces with gasoline and wipe them dry.

Replace a heavily oiled disc. Eliminate the cause of oiling.

- Reducing the force of the diaphragm spring

Replace the drive disc (basket)

- Strong wear or burning of the friction linings of the driven disk

Replace driven disc

- Damage or jamming of the clutch drive

Fix jams. Replace drive parts if necessary.

Clutch engages (not fully disengaging) Forward shifting is difficult, Reverse shifts noisily when transmission is good:

- Incorrect adjustment of the clutch drive (insufficient full pedal travel)

Adjust the drive

- Clutch cable jamming

Apply engine oil to the cable. If the cable is damaged, replace it.

- Weakening of rivets or breakage of friction linings, warping of the driven disk (end runout more than 0.5 mm)

Replace driven disc

- Strong and uneven wear, scuffing on the working surfaces of the flywheel or clutch pressure plate

Replace flywheel. If the surface of the pressure plate is damaged, replace the casing with the pressure plate assembly (clutch basket)

- Skewed or warped pressure plate

Replace cover with pressure plate assembly (clutch basket)

- Jamming of the hub of the driven disk on the splines of the input shaft of the gearbox

Clean the splines from dirt, eliminate minor damage with a needle file. In case of significant wear or damage to the splines, replace the driven disk or the gearbox input shaft.