Radiator Pressure Flush and Coolant Change
Note: For additional instructions on cleaning and flushing the cooling system, see the engine maintenance and operation manual.
- Drain the radiator, as follows.
- Disconnect the radiator inlet and outlet hose connections.
- Flush the radiator, as follows.
- Attach a flushing gun nozzle to the radiator outlet.
- Add water to the radiator until it is full.
- Apply no more than 20 psi (138 kPa) air pressure intermittently to help dislodge sediment buildup in the core.
Notice: When flushing the radiator, do not apply more than 20 psi (138 kPa) air pressure. Excessive pressure can damage the radiator or heater core.
- Drain the radiator, then flush the radiator until clean water flows from it. Remove the flushing gun.
- Close the petcock.
- Using clamps, connect the hoses to the radiator. Tighten the clamps 33 to 38 lbf·in(370 to 430 N·cm).
- Fill the cooling system with approved coolant. Refer to the engine manufacturer's service literature for specific coolant information. Refer to PartsPro (module 103) for coolant system capacities.
Warning: Drain the coolant only when the coolant and engine are cool. Draining it when these are hot could cause severe personal injury due to scalding.
Important: On vehicles with EPA10 compliant engines, the coolant capacity varies depending on the engine and accessory installation. After servicing the cooling system, always verify that the coolant level is between the MIN and MAX lines on the surge tank.