Cleaning Cooling System
- Start vehicle.
- After the vehicle has been bled and the coolant temperature is > 80°C, let the stationary vehicle run at medium speed for at least 15 minutes.
- Switch off engine.CAUTION:
- Danger of scalding.
- Allow the coolant to cool down before opening the coolant circuit.
- Coolant can be very hot.
- Wear suitable protective equipment.
- Slowly and carefully open the coolant expansion tank.
- Unscrew the coolant drain plug on the engine and drain and collect the radiator cleaning agent. Disposal should be carried out according to the country-specific legal requirements.
- Pull the radiator supply and return lines off the engine. To do so, undo the hose clamps, carefully pull off the hoses and allow the remaining liquid to run out.
- Rinse away any adhering oil in the coolant expansion tank with hot water.
- Connect the hoses again and tighten the hose clamps.
- Tighten drain plug on the engine with a tightening torque of 10 Nm (7.5 ft.lb) to 15 Nm (11.0 ft.lb).
- Fill the coolant circuit with water only and then bleed the cooling system according to the regulations.
- Start engine.
- After the vehicle has been bled and the coolant temperature is > 80°C, let the stationary vehicle run at medium speed for at least 15 minutes.
- Switch off engine.CAUTION:
- Danger of scalding.
- Allow the coolant to cool down before opening the coolant circuit.
- Coolant can be very hot.
- Wear suitable protective equipment.
- Carefully open the coolant expansion tank and reduce the existing residual pressure.
- Unscrew the coolant drain plug on the engine and drain the radiator cleaning agent.
- Pull the radiator supply and return lines off the engine. To do so, undo the screw-type hose clamps, carefully pull off the hoses and allow the remaining water to run out.
NOTE:
- All hoses which have been removed during work on the cooling system must be replaced.
- The Y-piece in the cooling system must be replaced.
- Remove and replace all hoses that need to be replaced or have been disconnected from the flange.
- Replace the Y-piece on the vehicle underbody.
- To do so, open the three fastening clamps with commercially available spring-band clamp pliers and pull off the Y-piece. Clean the flange with a cloth soaked in solvent naphtha and fit the new Y-piece.
- Clean the flanges of the coolant circuit. Use a cloth soaked in solvent naphtha and clean the flanges from which the coolant hoses have been disconnected.NOTE:
- The coolant hoses may only be coated with water as a lubricant to make the fitting of the hoses easier.
- Never treat coolant hoses with spray oil.
- Connect the new coolant hoses again and tighten the screw-type hose clamps or the spring-band clamps.
- Fit coolant drain plug with new sealing ring. Tightening torque 10 Nm (7.5 ft.lb) to 15 Nm (11.0 ft.lb).
- Fill the cooling system with a mixture of anti-freeze protection and water (mix ratio 50:50) and bleed.
- Check the cooling system for leaks.
- Fit the underside panel into place again.
- Perform an extended test drive with the vehicle and subsequently check the coolant level.