Fan with thermoviscous engagement
Removal
Note: On petrol models, this operation requires the use of a special tool to secure the radiator fan pulley to the fan support bracket. If you do not have such a tool and cannot borrow one from your dealer, you can make a replacement from a 4 mm diameter rod. For diesel models, to avoid damaging the fan pulley and related parts, it is recommended to purchase a branded fixing tool.
1. Disconnect the negative battery terminal. Remove the accessory drive belt (see Chapter 1).
2. Remove the screws and separate the plastic panels on the top and bottom of the radiator. Where provided, remove the coolant hose from the retainer on the top panel.
3. On models with a non-removable fan shroud, unhook the metal clips and separate the shroud from the radiator. Slide the shroud over the top of the fan and position it between the motor and fan blades - refer to paragraph 3.
4. On models with a split radiator shroud, remove the locking pin and turn the shroud ring to the left to release it from the radiator shroud. Route the shroud ring over the top of the fan and position it between the motor and fan blades - refer to paragraph 3.
5. Release the metal spring clips, then separate the fan shroud from the radiator and remove it from the engine compartment, followed by removing the shroud ring.
6. On gasoline models, rotate the fan pulley until the locking hole on the rear surface lines up with the notch on the fan support bracket. Insert the locking device (see point 1) so that the pulley is locked on the support bracket and cannot turn (see fig. 5.6).
Fig. 5.6. The radiator fan pulley shaft fixed with a homemade device (shown by arrow) — for clarity, the fan, clutch and pulley have been removed
7. On diesel models, the fan pulley shaft must be locked with a proprietary device that grips the edges of the fan pulley without removing the drive belt. Since the central bolt securing the viscous clutch is tightened with a high torque, it is not recommended to use a homemade device.
8. Loosen and remove the bolts, then separate the fan blade assembly from the clutch. On models with a non-separable shroud, remove the shroud from the engine compartment (see fig. 5.8).
Fig. 5.8. Loosen and remove the bolts and separate the fan blades from the viscous coupling
9. Loosen and remove the central bolt, then separate the engagement unit from the pulley shaft. If necessary, unscrew the bolts and remove the pulley from the shaft (see Fig. 5.9. a-g).
Fig. 5.9, a. Loosen and unscrew the central bolt...
Fig. 5.9. b....then separate the clutch from the pulley shaft
Fig. 5.9, c. If necessary, unscrew the bolts, remove the washer...
Fig. 5.9, g....and remove the pulley from the shaft
Installation
10. Installation is carried out in reverse order. Check that all bolts are tightened to the required torque (see fig. 5.10).
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Fig. 5.10. Make sure the coupling center bolt is tightened to the required torque
Fan with electromagnetic engagement
Removal
11. Disconnect the negative battery terminal. On 4-cylinder gasoline models, follow these steps:
- a) Drain the liquid from the cooling system (see Chapter 1).
- b) Remove the radiator (see paragraph 3).
- c) Remove the air cleaner (see Chapter 4).
12. Contact Chapter 1 and remove the accessory drive belt from the water pump pulley.
13. Loosen the central mounting bolt and remove the fan from the pump spindle (see fig. 5.13).
Fig. 5.13. Unscrew the central mounting bolt and remove the fan from the pump spindle
14. Loosen and remove the bolts, then remove the water pump pulley from the spindle (see fig. 5.14).
Fig. 5.14. Loosen and unscrew the bolts (shown by arrows), then remove the pump pulley from the shaft
15. On early models with split accessory drive belts, remove the three bolts securing the clutch housing to the water pump and pump bracket. Remove the clutch, disconnect the plug on the connector, and remove the unit from the vehicle (see Fig. 5.15, a, b).
Fig. 5.15. a. Location of left coupling mounting bolts (shown by arrows) - early models
1 Clutch housing
2 Connector plug
Fig. 5.15. b. Location of the coupling bracket mounting bolt (shown by arrow) - early models
16. On later models with a single drive belt, remove the bolts on the rear of the clutch housing that secure it to the backing plate. Disengage the clutch, disconnect the plug from the connector, and remove the unit from the engine.
Installation
17. Installation is carried out in the reverse order. Install the washers on the fan mounting bolt as shown in Fig. 5.17, and tighten all fasteners to the required torque.
Fig. 5.17. Fan mounting bolt, washer and spacer
1 Bolt
2 Plate washer
3 Spacer