TM-9-2320-361-24-2 Field Maintenance Manual Volume 2 for M44A2 Series Trucks
Page 854 of 1144
TM 9-2320-361-24-2 0426 00 0426 00-2 ENGINE COOLANT HEATER TESTING (Contd) PREPARATION WARNING • Do not perform engine coolant heater testing while smoking or within 50 feet of sparks or open flame. Fuel is flammable and can explode easily, causing injury or death to personnel and damage to equipment. • Exhaust gases can kill. Do not operate personnel heater in enclosed areas. Ensure work area is well ventilated and exhaust fumes are directed away from test area. NOTE • Perform “preparation” subtask before performing any test and perform “test equipment removal” after each test is complete. • Heater must be tested in same position as mounted on vehicle. • Use proper coolant required for engines which are being heated. Water cannot be used because the overheat switch and restriction thermostat are set for temperatures above the boiling point of water. • Coolant container must be vented and raised above the test apparatus in order for thermosyphon circulation to occur. • Fuel pump, fuel filter, heater, wiring harness, fuel tubing, control box, and coolant must be the same type used on vehicle. 1. Connect coolant heater (N) to test equipment using schematic on facing page.