Cooling System: Testing and Inspection
WM 190101 Checking cooling system on DFI engines
Tools
Tools and materials
Tools
Antifreeze tester => Antifreeze and battery acid tester FT 2030 WE 1037 or Antifreeze and battery acid tester SUN-Duo-Check WE 1036
Checking coolant antifreeze
Information
- The following diagram shows the scale used by Leitenberger. Antifreeze and battery acid tester FT 2030 WE 1037
- The scale can vary slightly, depending on the manufacturer.
- The ETHYLENE scale must be used for Porsche antifreeze.
- Other commercially available testers can also be used provided correct results are guaranteed.
Refractometer
1. Remove maintenance flap over the coolant expansion tank. => Maintenance cover
Maintenance cover
2. Using a pipette, take a sample from the coolant expansion tank. => Pipette
Pipette
3. Deposit a few drops on the test surface. => Depositing drops on the test surface
Depositing drops on the test surface
4. Close the light-diffusing lens. A closed film must form. => Closing the light-diffusing lens
Closing the light-diffusing lens
5. Using the refractometer, view against a very bright light source. A very clear light/dark limit emerges. The point of intersection between this line and the display scale marks the freezing point of the coolant.
6. A freezing point that is too low must be adjusted accordingly.
7. Close the maintenance flap.
Information
- The following table specifies how much coolant must be replaced by pure antifreeze in order to adjust the freezing point to -37 °C.
Checking the cooling system for leaks
1. Remove maintenance flap over the coolant expansion tank. => Maintenance cover
Maintenance cover
2. Check the cooling system for leaks. To do this, apply a test pressure of approx. 1.5 bar using the cooling system test device => Cooling system test device and check the hose connections for leaks. The pressure must not drop.
Cooling system test device
3. Check the coolant level. A graduated disc with a "min" and "max" marking is located in the opening of the expansion tank. The "min" level must be covered with coolant. => Graduated disc in the opening of the expansion tank
Graduated disc in the opening of the expansion tank
4. Screw cap back on the coolant expansion tank. => Cap on coolant expansion tank
Cap on coolant expansion tank
5. Close the maintenance flap.
6. Check radiator for external dirt. The radiators should not be excessively dirty. If necessary, they can be cleaned using a vacuum cleaner with a brush attachment.
Checking engine coolant level
Information
Test conditions for checking engine coolant level =>
- Engine cold
- Vehicle parked horizontally on level ground
1. Remove maintenance flap over the coolant expansion tank. => Maintenance cover
Maintenance cover
2. Unscrew cap on coolant expansion tank. => Cap on coolant expansion tank
Cap on coolant expansion tank
3. Check the engine coolant level. A graduated disc with a "Min" and "Max" marking is located in the opening of the expansion tank => Graduated disc in the opening of the expansion tank. The coolant must be above the "Min" level. If the coolant is below the "Min" level, top up with approved antifreeze. If there is considerable coolant loss, the cause must be investigated.
Graduated disc in the opening of the expansion tank
4. Screw cap back on the coolant expansion tank. => Cap on coolant expansion tank
Cap on coolant expansion tank
5. Close the maintenance flap.