Cooling System Specifications: Maintenance Jeep Cherokee II

MAINTENANCE SCHEDULE

Engine coolant protection should be checked once a year at the beginning of the winter season. Change engine coolant every 22,500 miles or 22 months. Maintain a 50/50 mixture of coolant and water.

DRAINING

FLUSHING

1. Reverse flushing is an effective means of removing cooling system rust and scale. Ensure heater control valve is closed (heater off). This will prevent coolant flow with scale and other deposits from entering heater core.
2. To flush radiator, connect flushing gun to water outlet of radiator and disconnect water inlet hose. To prevent flooding engine, use a hose connected to radiator inlet. Use air in short bursts to prevent damage to radiator. Continue flushing until water runs clear.
3. To flush engine, remove thermostat and replace housing. Connect flushing gun to water outlet of engine. Flush using short air bursts until water runs clean.
4. Flush heater core as described for radiator. Ensure heater control valve is set to maximum heat position before flushing heater.

REFILLING

1. Tighten radiator draincock and cylinder block drain plugs. Fill cooling system using a 50/50 mixture of water and coolant. Fill radiator to top. Install radiator cap.
2. On all models except Cherokee, Comanche and Wagoneer with 4.0L engine, add sufficient coolant to reserve bottle to raise coolant level to the FULL mark. Operate engine with radiator and reserve bottle caps in place. Turn heater control switch to the HEAT position.
3. On Cherokee, Comanche and Wagoneer models with 4.0L engine, fill coolant to the inside post in pressure bottle. The top of post is FULL mark. Operate engine with radiator and pressure bottle caps in place. Turn heater control switch to the HEAT position.
4. On all models, after engine has reached normal operating temperature, shut engine off and allow to cool. Add coolant to reserve bottle or pressure bottle as required.

Scheme 1

1. Visually inspect thermostat for corrosion and proper sealing of valve and seat. If okay, suspend thermostat and thermometer in a 50/50 mixture of coolant and water. (Scheme 1) Do not allow thermostat or thermometer to touch bottom of container. Heat water until thermostat just begins to open.
2. Read temperature on thermometer. This is initial opening temperature and should be within specification. Continue heating water until thermostat is fully open and note temperature. This is the fully opened temperature. If either reading is not to specification, replace thermostat. See «COOLING SYSTEM SPECIFICATIONS»(ref-50354-S30691544692001011600000) table.