Powertrain Secondary Cooling System

Powertrain Secondary Cooling System

Component Tests

Cooling System Pressure Test

WARNING: Always allow the engine to cool before opening the cooling system. Do not unscrew the coolant pressure relief cap when the engine is operating or the cooling system is hot. The cooling system is under pressure; steam and hot liquid can come out forcefully when the cap is loosened slightly. Failure to follow these instructions may result in serious personal injury.

1. Turn the engine OFF.

2. Check the coolant level. Adjust the coolant level as necessary.





3. Fit the Radiator/Heater Core Pressure Tester from the Pressure Test Kit to the degas bottle fill opening using the correct adapter.

4. NOTICE: Do not pressurize the cooling system beyond the maximum pressure listed in the specifications table or cooling system components can be damaged.

NOTE: If the plunger of the pressure tester is pressed too fast, an erroneous pressure reading will result.
Pressurize the cooling system to the maximum allowed pressure and hold for 2 minutes. If the pressure drops within this time, inspect for leaks and repair as necessary.

5. If no leaks are found detach the CAC (Charge Air Cooler) outlet pipe from the CAC (Charge Air Cooler) and inspect for leaks at the bottom of the CAC (Charge Air Cooler). Repair as necessary.

6. If no leaks are found at the CAC (Charge Air Cooler), the leak may be internal to the transmission fluid cooler. Check for transmission fluid in the coolant and for coolant in the transmission fluid. Repair as necessary.

7. If no transmission fluid was found in the coolant and no coolant found in the transmission fluid, the leak may be internal to the fuel cooler. Check the coolant for fuel and the fuel in the fuel conditioning module for coolant. Repair as necessary.

8. If no fuel is found in the coolant and no coolant is found in the fuel, the leak may be in the CAC (Charge Air Cooler), but too small for coolant to be noticeable at the bottom of the CAC (Charge Air Cooler). Leak test the CAC (Charge Air Cooler). For additional information, refer to Fuel Delivery and Air Induction. Repair as necessary.

9. If the CAC (Charge Air Cooler) tests OK, the leak may be internal to the EGR cooler. Leak test the EGR cooler. For additional information, refer to Emission Control Systems. Repair as necessary.

10. Release the system pressure and remove the Radiator/Heater Core Pressure Tester from the Pressure Test Kit. Check the coolant level and adjust as necessary.

Thermostat

A new thermostat should be installed only after the following tests and checks have been carried out:

- Pinpoint Test A, B or C

- Thermostat Visual Inspection

Thermostat Visual Inspection

1. Remove the thermostat. For additional information, refer to Thermostat- Low Temperature or Thermostat- High Temperature .

2. NOTE: The low temperature thermostat starts to open at 20°C (68°F), therefore the valve may not be fully seated at room temperature.

NOTE: The high temperature thermostat starts to open at 45°C (113°F), therefore the valve may not be seated if the ambient temperature is at or over this temperature.
Examine the thermostat for signs of damage including:
- Valve not fully seated (light visible through the valve)

- Foreign material lodged in the main valve

- Bent or broken frame or flange

- Bent or broken spring

- Bent or broken valve or valve stem

- Wax leaking from wax reservoir or a bulge in the reservoir

- Any other damage or distortion


3. NOTE: If no damage is found during the inspection, do not attempt to open the thermostat using hot water or other heat sources. This method is not an accurate means to test the function of the thermostat and may damage the thermostat.
If damage is found during the inspection, remove any foreign material or broken pieces and install a new thermostat.

4. If no damage is found during the inspection, continue troubleshooting the system concern. Go to the Symptom Chart for further instructions. Powertrain Secondary Cooling System

Radiator Leak Test, Removed From Vehicle

NOTICE: Never leak test an aluminum radiator in the same water that copper/brass radiators are tested in. Flux and caustic cleaners may be present in the testing tank and they will damage aluminum radiators.

NOTE: Clean the radiator before leak testing to avoid contamination of tank.

Leak test the radiator in clean water with pressurized air to the maximum pressure listed in the Specifications.