Water Pump: Service and Repair

Coolant Pump Removing and Installing

Special tools and equipment
- VAS 5024 Assembly tool for spring-type clips
- VAG 1306 Drip tray
- VAG 1331 Torque wrench (5-50 Nm)

Notes:
Always replace seals and gaskets.
Cover toothed belt with a cloth to protect it from coolant before removing coolant pump.
An additional electric pump for continued coolant circulation (After-run coolant pump -V51-) is installed in vehicles in hot countries. Fitting position and function, Fig. 1




Fig. 1 After-Run Coolant Pump -V51-




Engine Side Components Overview
1. Connection for thermostat
2. O-ring - Always replace
3. Coolant thermostat - Observe installation position
Checking: heat-up thermostat in water
Opening commences approximately 86° C
Opening lift min. 7 mm
4. Breather bolt. Torque Specification: 20 Nm (15 ft. lbs.)
5. Bolt. Torque Specification: 25 Nm (18 ft. lbs.)
6. Retaining clip - Check seated securely
7. Coolant - temperature sender (G62) for engine control module
8. Rear coolant hose
9. Lifting eye
10. Bolt. Torque Specification: 10 Nm (7 ft. lbs.)
11. Coolant hose
12. Front coolant hose
13. Cap. Test pressure: 1.4 - 1.6 bar (20 - 23 psi)
14. O-ring - Replace if damaged
15. Expansion tank
16. Upper coolant hose - Secured to radiator with retaining clip
Check securely seated
18. Rear toothed belt guard
19. Gasket - Always replace
20. Coolant pump - Check for ease of movement
21. Lower coolant hose
22. Oil cooler
23. Belt pulley for viscous fan coupling
Torque Specification for 3 securing bolts 30 Nm (22 ft. lbs.)
24. Radiator fan
25. Viscous fan coupling - Observe left hand thread
Tightening torque only valid for open jaw spanner 3312
Tighten to 40 Nm (30 ft. lbs.)
26. Bracket for viscous fan coupling
27. From bottom of radiator

Removing

- Drain coolant, refer to Coolant - Service and Repair - Procedures Service and Repair

- Bring lock carrier into service position, refer to Body and Frame - Service and Repair. [1][2]Procedures

- Remove viscous fan coupling, refer to Cooling Fan - Fan Clutch - Service and Repair. Service and Repair

- Remove ribbed belt, refer to Drive Belt - Service and Repair. Service and Repair

- Remove toothed belt guard.

- Loosen tensioner and remove toothed belt from camshaft sprockets, refer to Timing Belt - Service and Repair. Procedures

- Remove bracket for viscous fan coupling.




- Unscrew coolant pump securing bolts -1 and remove coolant pump -2-.

Installing

Installation is carried out in the reverse order, when doing this note the following:

- Fit new gasket -3- onto water pump flange.






- Insert coolant pump -2- into cylinder block and tighten securing bolts -1-.

- Tightening torque: 10 Nm

- Installing toothed belt and adjusting timing

- Install toothed belt guard.

- Install ribbed belt.

- Fill with coolant.