Coolant: Service and Repair
Draining and filling in coolant (includes bleeding)
Draining coolant
Information
To facilitate assembly of coolant pipes and hoses, smear with Kluber Syntheso Glep or alternatively Kluberplus S06-100 assembly gel.
Information
Check Henn coupling O-rings and replace them if necessary.
Clean plug connection and coolant hoses before assembly.
Coat O-rings and coolant hoses with Kluberplus Gel (Part No. 000.043.205.93).
Remove stoppers before fitting the coolant lines and hoses.
Warning
Hot pressurized coolant.
Danger of scalding and burning.
- Only work on the coolant system when the engine is "cool".
- Wear protective clothes, gloves and goggles.
1. Open cap on the reservoir -1- and remove it.
Cap for coolant reservoir
2. Remove rear underbody panel.
Warning
Coolant is corrosive and hazardous to health.
Risk of skin and eye irritation.
- Wear protective gloves and goggles.
- If you come into contact with coolant, wash off immediately with plenty of warm water.
3. Place a suitable container under the vehicle to collect coolant at each of the drain outlets. The container can be secured on a transmission jack, for example, with a tensioning strap.
4. Unscrew drain plugs on the coolant hoses.
Coolant drain plug
5. Open inlet and outlet hoses on the coolant pipes. To do this, first pull off the spring clamps on the Henn coupling and then the hoses.
Henn coupling on coolant hose
6. Open the coolant hoses at the coolers. To do this, first pull off the spring clamps and then the hoses.
Filling in coolant and bleeding the system
Warning
Coolant is corrosive and hazardous to health.
Risk of skin and eye irritation.
- Wear protective gloves and goggles.
- If you come into contact with coolant, wash off immediately with plenty of warm water.
Information
The process of filling and bleeding the cooling system continues to be performed using the special tool Radiator filling device 9696.
Information
The quantity of coolant available should exceed the amount required to fill the system by about two liters in order to prevent air being sucked in.
An antifreeze content of -35 °C corresponds to a mixture of 50:50 (antifreeze: water).
Information
If a vacuum does not build up, there is a leaking valve in the coolant circuit.
Deformation of the rubber hoses of the cooling system is normal.
When the pressure gauge pointer is in the green area of the display scale, a sufficient vacuum has been built up.
After both shutoff valves on the vacuum pressure gauge have been closed and the compressed air supply has been disconnected, the vacuum must not drop. If the vacuum drops within approx. 30 seconds, there is a leak in the coolant circuit.
1. Fit new seals on drain plug and then tighten the drain plug. - Tightening torque: 10 Nm (7.5 ftlb.) +5 Nm (+3.5 ftlb.)
2. Fit the spring clamps on the Henn couplings.
Information
Check Henn coupling O-rings and replace them if necessary.
Clean plug connection and coolant hoses before assembly.
Coat O-rings and coolant hoses with Kluberplus Gel (Part No. 000.043.205.93).
Remove stoppers before fitting the coolant lines and hoses.
Information
To facilitate assembly of coolant pipes and hoses, smear with Kluber Syntheso Glep or alternatively Kluberplus S06-100 assembly gel.
Information
The coolant hoses must engage audibly when pushed into the flanges (Henn coupling).
3. Fit new O-rings on coolant hoses (if required). Pull to check that the connections are secure.
4. Screw cap adapter for coolant reservoir (K 22) onto the reservoir and attach the flexible extension (Fz 100) to the cap.
Adapter K22 on coolant reservoir
5. Connect the vacuum pressure gauge of the bleeder tool to the flexible extension. When doing so, ensure that both shutoff valves are closed (positioned at 90° with respect to flow direction).
6. Connect the Venturi nozzle to the vacuum pressure gauge.
Venturi nozzle on vacuum pressure gauge
Information
The bleeding process is completed more quickly if the canister is positioned at the same height as the coolant reservoir.
7. Place a canister with a sufficient amount of coolant and with an antifreeze content for -35 °C behind the vehicle close to the reservoir.
8. Push the filler hose of the vacuum pressure gauge -5- onto the canister connection. Draw off the return line -6- of the Venturi nozzle into a second container.
Special canister filling tool
Information
A hissing sound after connecting the compressed air supply is usual.
9. Connect the compressed air supply to the Venturi nozzle.
Compressed air supply on Venturi nozzle
10. Open both shutoff valves on the vacuum pressure gauge until the transparent filler hose is completely filled with coolant.
Shutoff valves open
11. Close the left shutoff valve on the vacuum pressure gauge and allow a vacuum to build up in the coolant circuit.
Left-hand shutoff valve closed
12. When there is sufficient vacuum in the cooling system, close right shutoff valve and then disconnect the compressed air supply.
Vacuum established (pointer in green region)
13. Open the left-hand shutoff valve on the vacuum pressure gauge (right-hand valve closed -Arrow-). The cooling system is then filled.
Left-hand shut off valve open - right-hand valve (arrow) closed
14. When the cooling system no longer contains a vacuum (vacuum pressure gauge shows zero), i.e. no more coolant is being sucked out of the canister, open right-hand shutoff valve.
15. Then remove the complete filling device 9696 (including cap K 22).
16. If necessary, fill the coolant reservoir with coolant up to the maximum marking and screw on the cap of the reservoir (do not tilt).
Subsequent Work
1. Check coolant line connections and hoses for leaks.
2. Completely install rear underbody panel.
3. Test drive the vehicle. After the test drive and when the engine is still at operating temperature, accelerate briefly to approx. 6,000 rpm a number of times at idle speed in order to fully ventilate the system.
4. Check the fluid level by examining the markings on the reservoir. If necessary, correct the coolant level after the engine has cooled.