Coolant: Service and Repair
DRAINING
WARNING: DO NOT REMOVE THE CYLINDER BLOCK DRAIN PLUGS OR LOOSEN THE RADIATOR DRAIN-COCK WITH THE COOLING SYSTEM HOT AND UNDER PRESSURE. SERIOUS BURNS FROM COOLANT CAN OCCUR.
1. DO NOT remove the pressure cap first. With the engine cold, raise and support the vehicle on a hoist and locate the radiator draincock.
NOTE: Radiator draincock is located on the left/lower side of radiator facing to rear of vehicle.
2. Attach one end of a hose to the draincock (2). Put the other end into a clean container. Open draincock and drain the coolant from the radiator. This will also empty the coolant recovery reservoir (1). When the tank is empty, remove the pressure cap and continue draining the cooling system.
REFILLING
1. Tighten the radiator draincock and the cylinder block drain plug(s) (if removed).
CAUTION: Failure to purge air from the cooling system can result in an overheating condition and severe engine damage.
2. Fill system using a 50/50 mixture of antifreeze/coolant and low mineral content water. Fill the coolant recovery reservoir to service line and install pressure cap.
NOTE: The engine cooling system will push any remaining air into the coolant recovery reservoir within about an hour of normal driving. As a result, a drop in coolant level in the coolant recovery reservoir may occur. If the engine cooling system overheats and pushes coolant into the overflow side of the coolant recovery reservoir, this coolant will be drawn back into the cooling system ONLY IF THE PRESSURE CAP IS LEFT ON RESERVOIR. Removing the pressure cap breaks the vacuum path between the two reservoir sections and the coolant will not return to cooling system.
3. With the heater control unit in the HEAT position, operate the engine with the coolant recovery reservoir cap in place.
4. Add coolant to the coolant recovery reservoir as necessary. Only add coolant to the coolant recovery reservoir when the engine is cold. Coolant level in a warm engine will be higher due to thermal expansion.
NOTE: The coolant recovery reservoir has two chambers. Coolant will normally only be in the outboard (larger) of the two. The inboard chamber is only to recover coolant in the event of an overheat or after a recent service fill. The inboard chamber should normally be empty. If there is coolant in the overflow side of the coolant recovery reservoir (after several warm/cold cycles of the engine) and the coolant level is above the cold full line when cold, disconnect the end of the overflow hose at the radiator and lower it into a clean container. Allow the coolant to drain into the container until emptied. Reconnect the overflow hose to radiator.
REVERSE FLUSHING
CAUTION: The cooling system normally operates at 97 - 110 kPa (14 - 16 psi) pressure. Exceeding this pressure may damage the radiator or hoses.
Reverse flushing of the cooling system, is the forcing of water through the cooling system in the reverse direction of normal flow. This is done using compressed air and water. It is usually only necessary when the cooling system is extremely contaminated and evidence of partial plugging is evident.
CHEMICAL CLEANING
If visual inspection indicates the formation of sludge or scaly deposits, use a radiator cleaner (Mopar Radiator Kleen or equivalent) before flushing. This will soften scale and other deposits and aid the flushing operation.
CAUTION: Be sure instructions on the container are followed.
REVERSE FLUSHING RADIATOR
Disconnect the radiator hoses from the radiator. Attach a section of radiator hose to the radiator bottom outlet fitting and insert the flushing gun. Connect a water supply hose and air supply hose to the flushing gun.
CAUTION: The cooling system normally operates at 97 - 110 kPa (14 - 16 psi) pressure. Exceeding this pressure may damage the radiator or hoses.
Allow the radiator to fill with water. When the radiator is filled, apply air in short blasts allowing the radiator to refill between blasts. Continue this reverse flushing until clean water flows out through the rear of the radiator cooling tube passages. For more information, refer to operating instructions supplied with the flushing equipment.