Cooling system pressure test
WARNING: Do not, under any circumstances, remove the sealed cap of the coolant expansion tank while the engine is running. To avoid scalding yourself with hot water or steam, take extra care when removing the coolant expansion tank seal when the cooling system is warm. Wait for the engine to cool down, wrap the sealed cap of the expansion tank with a thick cloth and slowly unscrew it until the pressure starts to relieve; step back while depressurizing. After making sure that the pressure is completely relieved and without removing the cloth, turn and remove the pressure-tight cap of the expansion tank. Failure to follow these instructions may result in damage to the cooling system, engine and/or personal injury.
1. Stop the engine.
2. Open the hood and install fender guards.
3. Carefully remove the expansion tank seal to relieve pressure in the cooling system. If necessary, add coolant to the expansion tank.
4. Install the pressure test equipment on the cooling system following the manufacturer's instructions. Replace the expansion tank seal (if the pressure test equipment is not installed on the expansion tank).
5. Raise the pressure in the cooling system to the lower limit that is set for the sealed cap of the expansion tank.
6. Observe the pressure gauge for approximately two minutes. During this period of time, the pressure should not fall.
- If the system holds pressure, continue with step 7.
- If the pressure drops, check the entire cooling system for leaks. If a leak in the cooling system cannot be found, also refer to checks on the engine system. Repair any leaks found and recheck the system.
8. Check if there is a blockage in the radiator bypass hose that could obstruct the supply/return of coolant from the expansion tank.
9. Perform the coolant expansion tank seal test described in this section.
Pressure test of the sealed cap of the expansion tank of the cooling system
WARNING: Do not, under any circumstances, remove the sealed cap of the coolant expansion tank while the engine is running. To avoid scalding yourself with hot water or steam, take extra care when removing the coolant expansion tank seal when the cooling system is warm. Wait for the engine to cool down, wrap the sealed cap of the expansion tank with a thick cloth and slowly unscrew it until the pressure starts to relieve; step back while depressurizing. After making sure that the pressure is completely relieved and without removing the cloth, turn and remove the pressure-tight cap of the expansion tank. Failure to follow these instructions may result in damage to the cooling system, engine and/or personal injury.
1. Remove the sealed cap from the expansion tank of the cooling system.
2. Wash the cap with water around the rubber seal and safety valve. In accordance with the manufacturer's instructions, install an airtight expansion bottle cap on the test equipment.
NOTE: If the test equipment is pressurized too quickly, incorrect pressure readings may occur.
3. Slowly pressurize the system until the pressure gauge stops rising; record the highest pressure reading noted.
4. Relieve pressure and repeat step 3 at least twice to ensure readings are consistent and consistent.
5. If the pressure gauge readings are not correct, install a new sealed cap on the expansion tank of the cooling system.
Thermostat check
Remove the thermostat. For more information refer to: Thermostat (303-03B Engine cooling - 2.2L Duratorq - Td4, Removal and installation).
Check for visual damage, note the opening temperature of the thermostat and immerse it in water. Heat water until this temperature is reached. This should open the thermostat. If the thermostat does not start to open, install a new thermostat. For more information refer to: Thermostat (303-03B Engine cooling - 2.2L Duratorq - Td4, Removal and installation).
If the thermostat starts to open, continue to heat the water until the thermostat is fully open, 5.8mm or more from the seat. If the thermostat does not open fully, install a new thermostat. For more information refer to: Thermostat (303-03B Engine cooling - 2.2L Duratorq - Td4, Removal and installation).
Checking the Radiator for Leaks - With Removal from Vehicle
CAUTION: Do not test an aluminum heatsink for leaks in the same water used to test copper/brass heatsinks. Flux and alkaline cleaners may be present in the water used for testing and will corrode the aluminum. If there is no separate container, drain the water from the test container and rinse it before checking the aluminum radiator.
Before starting the test, clean the radiator so as not to contaminate the test container. Check the radiator for leaks in clean water at 138 kPa air pressure.
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