Engine Cooling System Diagnosis: Maintenance Dodge Pickup R2500

REVERSE FLUSHING

Reverse flushing of the cooling system is the forcing of water through the cooling system. This is done using air pressure in the opposite direction of normal coolant flow. It is usually only necessary with very dirty systems with evidence of partial plugging.

REVERSE FLUSHING RADIATOR

Disconnect the radiator hoses from the radiator inlet and outlet. Attach a section of the 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.

Allow the radiator to fill with water. When the radiator is filled, apply air in short blasts. Allow the radiator to refill between blasts. Continue this reverse flushing until clean water flows out through the rear of the radiator cooling tube passages.

REVERSE FLUSHING ENGINE

Drain the cooling system. Remove the thermostat housing and thermostat. Install the thermostat housing. Disconnect the radiator upper hose from the radiator, and attach the flushing gun to the hose. Disconnect the radiator lower hose from the water pump, and attach a lead-away hose to the water pump inlet fitting.

Connect the water supply hose and air supply hose to flushing gun. Allow the engine to fill with water. When the engine is filled, apply air in short blasts, allowing the system to fill between air blasts. Continue until clean water flows through the lead-away hose.

Remove the lead-away hose, flushing gun, water supply hose and air supply hose. Remove the thermostat housing and install the thermostat. Install the thermostat housing with a replacement gasket. Connect the radiator hoses. Refill the cooling system with the correct antifreeze/water mixture. Refer to STANDARD PROCEDURE - REFILLING COOLING SYSTEM - 3.7L/4.7L/5.7L ENGINE or STANDARD PROCEDURE - REFILLING COOLING SYSTEM - 5.9L/8.0L ENGINE .

STANDARD PROCEDURE - DRAINING COOLING SYSTEM 3.7L/4.7L/5.7L ENGINE

1. With the engine cold, raise 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. Put the other end into a clean container. Remove the radiator cap, open the draincock and drain the cooling system.
3. If draining the entire engine is required, remove the cylinder block drain plugs.

STANDARD PROCEDURE - REFILLING COOLING SYSTEM - 3.7L/4.7L/5.7L ENGINE

DO NOT WASTE REUSABLE COOLANT. If the solution is clean, drain the coolant into a clean container for reuse.

1. Install the cylinder block drain plugs (if removed). Coat the threads with Mopar® Thread Sealant with Teflon.
2. Close the radiator draincock. CAUTION: Failure to purge air from the cooling system can result in an overheating condition and severe engine damage.
3. Fill system using a 50/50 mixture antifreeze and low mineral content water. Stop filling when the level in the degas bottle has reached the top of the COLD FILL RANGE.
4. Start and operate the engine until the thermostat opens (upper radiator hose is warm to the touch).
5. If necessary, add a 50/50 mixture of anti-freeze and water to the degas bottle to maintain the proper coolant level in the degas bottle.
6. Install the radiator cap.

STANDARD PROCEDURE - DRAINING COOLING SYSTEM - 5.9L/8.0L ENGINE

DO NOT WASTE reusable coolant. If solution is clean, drain coolant into a clean container for reuse.

1. Attach one end of a hose to the draincock. Put the other end into a clean container.
2. DO NOT REMOVE THE RADIATOR CAP when draining the coolant from the reservoir/overflow tank. Open radiator draincock and when the tank is empty, remove the radiator cap and continue draining the cooling system.
3. If draining the entire engine, remove the cylinder block drain plugs. Refer to (Схема №17)

STANDARD PROCEDURE - REFILLING COOLING SYSTEM - 5.9L/8.0L ENGINE

DO NOT WASTE reusable coolant. If solution is clean, drain coolant into a clean container for reuse.

Clean cooling system prior to refilling. Refer to STANDARD PROCEDURE - COOLING SYSTEM CLEANING/REVERSE FLUSHING .

1. Install cylinder block drain plugs. Coat the threads with Mopar® Thread Sealant with Teflon.
2. Close radiator petcock.
3. Fill cooling system with a 50/50 mixture of water and antifreeze.
4. Fill coolant reserve/overflow tank to MAX mark on bottle.
5. Start and operate engine until thermostat opens (upper radiator hose warm to touch).
6. If necessary, add a 50/50 water and antifreeze mixture to the coolant reserve/overflow tank. This is done to maintain coolant level between the MAX and MIN marks. The level in the reserve/overflow tank may drop below the MIN mark after three or four warm-up and cool-down cycles.

STANDARD PROCEDURE - DRAINING COOLING SYSTEM - 5.9L DIESEL ENGINE

DO NOT WASTE reusable coolant. If the solution is clean, drain the coolant into a clean container for reuse.

1. Start the engine and place the heater control temperature selector in the Full-On position.
2. Turn the ignition off.
3. DO NOT remove radiator cap when draining coolant from reserve/overflow tank. Open radiator drain plug and when tank is empty, remove radiator cap. If the coolant reserve/overflow tank does not drain, refer to «DIAGNOSIS AND TESTING»(ref-189654-S16533620042005091200000) . The coolant need not be removed from tank unless the system is being refilled with fresh mixture.
4. Remove radiator pressure cap.

STANDARD PROCEDURE - REFILLING COOLING SYSTEM - 5.9L DIESEL ENGINE

Clean cooling system prior to refilling. Refer to STANDARD PROCEDURE - COOLING SYSTEM CLEANING/REVERSE FLUSHING .

1. Close radiator drain plug. CAUTION: Due to the use of the one-way check valve, the engine must not be operating when refilling the cooling system NOTE: The diesel engine is equipped with two one-way check valves (jiggle pins). The check valves are used as a servicing feature, and will vent air when the system is being filled. Water pressure (or flow) will hold the valves closed.
2. Fill the cooling system with a 50/50 mixture of water and antifreeze.
3. Fill coolant reserve/overflow tank to the FULL mark.
4. Start and operate engine until thermostat opens. Upper radiator hose should be warm to touch.
5. If necessary, add 50/50 water and antifreeze mixture to the coolant reserve/overflow tank to maintain coolant level. This level should be between the ADD and FULL marks. The level in the reserve/overflow tank may drop below the ADD mark after three or four warm-up and cool-down cycles.