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Pressure Test

Pressure Test

WARNING: Never remove the expansion tank cap under any circumstances while the engine is operating. Failure to follow these instructions may result in damage to the cooling system or engine and/or personal injury. To avoid having scalding hot water or steam blow out of the cooling system, use extreme care when removing the expansion tank cap from a hot cooling system. Wait until the engine has cooled, then wrap a thick cloth around the expansion tank cap and turn it slowly until the pressure begins to release, step back while the pressure is released from the cooling system. When certain all the pressure has been released (still with a cloth) turn and remove the expansion tank cap. Failure to follow these instructions may result in personal injury.

1. Switch the engine off.
2. Open the hood and install protective fender covers.
3. Carefully remove the coolant expansion tank cap from the coolant expansion tank to relieve pressure in the cooling system. Add coolant to coolant expansion tank as necessary.
4. Install the adapter fitting from Pressure Tester tightly between overflow/air purge nipple and overflow/air purge hose at the coolant expansion tank. Reinstall the coolant expansion tank cap.
5. Attach the pressure pump and gauge to the adapter fitting and pressurize the cooling system to the coolant expansion tank cap lower limit. Refer to Specification.
6. Pressurize the cooling system. Observe the gauge reading for approximately two minutes. Pressure should not drop during this time.If system holds pressure, proceed to Step 8.If the pressure drops, check for leaks at the engine to heater core hoses, engine to radiator hoses, bypass hose, water valve hose (if applicable), thermostat housing gasket, radiator and heater core, etc. Also refer to engine system checks if a leak cannot be located in the cooling system. Correct any leaks found and recheck the system.
7. Release the system pressure by loosening the coolant expansion tank cap. Check the coolant level. Replenish as necessary with the correct coolant solution.
8. Check the radiator overflow hose for any obstructions which may block the flow of coolant either to or from the coolant expansion tank.
9. Conduct the expansion tank cap Pressure Test in this section.