COOLING SYSTEM Return to Main Table of Contents GENERAL............................................................................................... 2 COOLING SYSTEM .................................................................................. 7 RADIATOR ............................................................................................... 9 ENGINE COOLANT PUMP ..................................................................... 12 THERMOSTAT.................................................
5-2 GENERAL GENERAL SPECIFICATIONS Cooling method Water-cooled, pressurized. Forced circulation with electrical fan Cooling system Quantity 6 lit (6.3 U.S.qts., 5.2 Imp.qts.
GENERAL TIGHTENING TORQUE Generator support nut Generator adjuster lock bolt Engine coolant pump to cylinder block Engine coolant pump to cylinder block (generator brace mounting) Engine coolant pump pulley Engine coolant temperature sender Engine coolant temperature sensor Engine coolant outlet fitting bolt 25-3 Nm kg.cm Ib.
GENERAL 25-4 TROUBLESHOOTING Symptom Probable cause Remedy Low coolant level Leakage of coolant Heater or radiator hose Faulty radiator cap Thermostat housing Radiator Engine coolant pump Repair or replace parts Tighten or replace clamps Replace gasket or housing Replace Replace parts Clogged radiator Foreign material in coolant Replace coolant Abnormally high coolant temperature Faulty thermostat Faulty radiator cap Restricted to flow in cooling system Loosen or missing drive belt Faulty engine
GENERAL COOLANT LEAK CHECK 1. Loosen the radiator cap. 2. Confirm that the coolant level is up to the filler neck. 3. Install a radiator cap tester to the radiator filler neck and apply 150 kPa (21 psi, 1.53 kg/cm2) pressure. Hold for two minutes, while checking for leakage from the radiator, hose or connections. CAUTIONS 1) Radiator coolant may be extremely hot. Do not open the system while hot, or scalding water could spray out causing personal injury. Allow vehicle to cool before servicing this system.
GENERAL RELATION BETWEEN COOLANT CONCENTRATION AND SPECIFIC GRAVITY Example The safe operating temperature is -15°C (5°F) when the measured specific gravity is 1.058 at coolant temperature of 20°C (68°F). CAUTION If the concentration of the coolant is below 30%, the anti-corrosion property will be adversely affected. In addition, if the concentration is above 60%, both the anti-freeze and engine cooling properties will decrease affecting the engine adversely.
COOLING SYSTEM DRIVE BELT TENSION ADJUSTMENT The belt must be adjusted to the following specifications. 1. When 100 N (22 lb) (tension or compression) is given perpen dicularly to belt at center “A”, sag is to be "L" mm. 2. Or, tension gauge must read “T” at center “A”. New belt installed Used belt installed Deflection Tension (T) (0.30-0.35 in.) 10.0 mm (0.39 in.) 50 - 70 kg (110-154 lb) 40 kg (88 lb) 7.5 - 9.
25-8 COOLING SYSTEM DRIVE BELT AND PULLEY Removal 1. Loosen generator support nut “A” and the belt tension adjuster lock bolt “B”. 2. Rotate the adjuster bolt counterclockwise to relieve belt tension, and remove the belt. 3. Remove the water pump pulley bolts and remove the engine coolant pump pulley. Tightening torque Generator support nut A ................................... 20-25 Nm (200-250 kg.cm, 14-18 Ib.ft) Adjuster lock bolt B .......................................... 12-15 Nm (120-150 kg.
RADIATOR RADIATOR COMPONENTS 25-9
25-10 RADIATOR REMOVAL 1. Disconnect the fan motor plug. 2. Set the warm engine coolant flow control knob of the heater control to the hot position. 3. Loosen the radiator drain plug to drain coolant. 4. Disconnect the upper and lower hose, and the overflow tube. 5. For vehicles with an automatic transaxle, disconnect the oil cooler hoses from the automatic transaxle.
RADIATOR 9. Check for continuity with thermo sensor on water outlet fitting in hot water. Continuity at 102-108°C (215.6-226.4oF) No continuity at 98°C (208.4oF) or more Radiator Fan Motor 1. Check to be sure that the radiator fan rotates when battery voltage is applied between the terminals (as shown in the figure). 2. Check to see that abnormal noises are not produced while the motor is turning. INSTALLATION 1. Fill the radiator and reservoir tank with a fresh coolant mixture. 2.
25-12 ENGINE COOLANT PUMP COMPONENTS TORQUE : Nm (kg.cm, Ib.
ENGINE COOLANT PUMP REMOVAL 1. Drain the coolant and disconnect the radiator outlet hose and engine coolant by-pass hose from the engine coolant pump. 2. Remove the drive belt and engine coolant pump pulley. 3. Remove the timing belt covers and the timing belt tensioner. 4. Remove the engine coolant pump mounting bolts and then remove the generator brace. 5. Remove the engine coolant pump assembly from the cylinder block. INSPECTION 1.
25-14 THERMOSTAT THERMOSTAT TORQUE : Nm (kg.cm, Ib.ft) REMOVAL AND INSPECTION 1. 2. 3. 4. 5. 6. Drain the coolant down to thermostat level or below. Remove the water outlet fitting and gasket. Remove the thermostat. Heat the thermostat as shown in the illustration. Check to see if the valve operates properly. Check to determine the temperature at which the valve begins to open. Valve opening temperature ..................................... 88oC(190oF) o o Full opening temperature .....................
ENGINE COOLANT TEMPERATURE SENDER, SENSOR ENGINE COOLANT TEMPERATURE SENDER, SENSOR COMPONENTS TORQUE : Nm (kg.cm, Ib.ft) REMOVAL 1. Drain the coolant down to sender level or below. 2. Disconnect the battery ground cable and disconnect the engine harness. 3. Remove the engine coolant temperature sender and sensor. INSPECTION 1. Heat the engine coolant temperature sender by submerging it in hot water. 2. Check that the resistance is within the specified range. Resistance .......................... 90.
25-16 ENGINE COOLANT TEMPERATURE SENDER, SENSOR Engine Coolant Temperature Sensor 1. Heat the sensor by submerging it in hot water. 2. Check that the resistance is within the specified range. at 20°C (68°F) Resistance ...................... 2.21-2.69 264-328 at 80°C (176°F) INSTALLATION 1. Apply sealant to the threaded portion and tighten to the specified torque. Engine coolant temperature sender ............................ Three bond NO.2310 or equivalent Engine coolant temperature sensor .............
ENGINE COOLANT HOSE AND PIPE ENGINE COOLANT HOSE AND PIPE COMPONENTS TORQUE : Nm (kg.cm, Ib.ft) INSPECTION Check the engine coolant pipe and hose for cracks, damage, or restrictions. Replace if necessary. INSTALLATION Fit O-ring in the groove provided at engine coolant inlet pipe end, wet the periphery of O-ring and inset engine coolant inlet pipe. NOTE 1. Do not apply oils or greases to water pipe O-ring. 2. Keep the engine coolant pipe connections free of sand, dust, etc. 3.
