Thermostat: Service and Repair

Removing and installing coolant regulator (thermostat)














Special tools








Component overview

Removing thermostat
^ Remove intake distributor.
^ All seals and O-rings must be replaced.

1. Position the vehicle at the specified points using a lifting platform.
2. Open the bonnet.

Note:
^ The coolant filled in at the factory is intended for lifetime cooling and, thus, need not be changed. This coolant must not be mixed with other coolants.
^ Only original Porsche antifreeze should be used when changing or topping up the coolant.





3. Open maintenance cover.

Caution: Danger of scalding!
^ Coolant can be extremely hot and pressurized.
^ Only open the cooling system when it is cold.
^ Wear gloves.





4. Carefully open the cap on the coolant expansion tank. Unscrew the cap in a counterclockwise direction.
5. Open cap on the expansion tank and remove it.





6. Remove underside panel. To do this, undo screws -1, 2 and 3-.





7. Release the front apron on the underside.





8. Remove the sheetmetal brace under the radiator. To do this, loosen the four fastening screws.





9. Drain cooling system. Remove the drain plug from the radiator, drain the coolant into a container and dispose of it according to the applicable national laws if no longer required.
10. Fit a new drain plug on the radiator and tighten it.
11. Install the sheetmetal brace under the radiator. Tighten the 4 fastening screws to 23 Nm (17 ft. lbs.).





12. Remove the two coolant lines on the thermostat housing cover. To do this, remove the spring band clamps and pull off the hoses.

Note: To ease removal, spray the pulley from the rear side with an anti-corrosion agent.





13. Unscrew the three fastening screws on the coolant pump pulley. Wrench size: T 40.

Warning: Risk of damage! Never remove a drive belt when it is hot.





14. Mark the direction of running of the drive belt with chalk.





15. Use an open-ended wrench (a/f 30) to turn the belt tensioner clockwise and, at the same time, remove the drive belt from the tensioning roller. Relieve the belt tensioner carefully. Remove the drive belt from the coolant pump.

Warning: Risk of damage!
^ The pulleys on engine accessories are made of plastic. Do not use damaged pulleys.
^ The pulley is sensitive to impacts.
^ Do not prize off the pulley with a screwdriver.





16. Remove the three loosened fastening screws on the pulley and remove it.





17. Pull off the cable duct over the coolant pump in an upward direction.
18. Undo the upper fastening screw of the oil dipstick.





19. Disconnect the coolant return on the generator. To do this, open the spring band clamp and pull off the hose. Collect the draining coolant.





20. Remove the coolant return line on the thermostat housing. To do this, loosen the fastening screw and pull out the line.





21. Disconnect the vent line for the cylinder heads. To do this, press on the grooved surfaces of the button and pull off the plugs.





22. Undo the three rear fastening screws of the heating pipe.





23. Undo the thermostat housing cover. To do this, the sequence shown in the figure must be adhered to.





24. Lift the housing cover. Remove the thermostat with the special tool.

Installing thermostat

Note: All seals between opened sealing surfaces must be replaced.





1. Insert thermostat in the cover and twist it until the two sheetmetal edges are positioned to the left and right of the holder.





View shows fitting using the special tool

2. Replace inner and outer seal in the thermostat housing.





3. Position thermostat housing cover and tighten the fastening screws (M6 x 25) to 10 Nm (7.5 ft. lbs.).





4. Tighten the three rear fastening screws (M6 x 16) of the heating pipe to 10 Nm (7.5 ft. lbs.).





5. Connect the vent lines for the cylinder heads. The plugs must engage audibly.





6. Fit the coolant line for the generator. Insert the line in the thermostat housing cover and tighten the fastening screw (M6 x 12) to 10 Nm (7.5 ft. lbs.).





7. Then push the holder onto the timing case cover under the cable duct and tighten the screw to 10 Nm (7.5 ft. lbs.).





8. Push on the coolant line for the generator and fit the spring band clamp.





9. Tighten the upper fastening screw (M6 x 16) of the oil dipstick to 10 Nm (7.5 ft. lbs.).





10. Push on the cable duct onto the retaining bracket over the coolant pump.





11. Fit the pulley on the coolant pump. Screw in the three fastening screws by hand.





12. Mount the drive belt. To do this, turn the belt tensioner clockwise and thread the drive belt around all the pulleys. Then carefully relieve the tensioning roller.
13. Check whether the drive belt is correctly installed.





14. Tighten the three fastening screws to 23 Nm (17 ft. lbs.).





15. Fit the coolant feed and return line on the thermostat housing cover.
16. Install intake distributor.
17. Fill the cooling system and check for leaks.





18. If necessary, fill the coolant expansion tank with coolant to the maximum marking.

Note: The system can be checked for leaks, if necessary.





Figure shows check for leaks





19. Screw on the cap of the expansion tank.
20. Close the maintenance cover.





21. Reinstall the complete engine guard.
22. Conduct a test drive with the vehicle. Check the fluid level in the expansion tank after the coolant circuit has cooled again and, if necessary, fill up to the max marking with coolant.





Tightening torques