TM10-3930-660-20 7-3. RADIATOR -  SERVICE/REPLACE/TEST (Cont’d) 4. CHECK COOLING SYSTEM FOR LEAKAGE. a. Check radiator for visible leakage. Replace radiator if leaks are present. Refer to REMOVAL and INSTALLATION sections of this paragraph. b. Check all connections and hoses of cooling system for visible leakage. Replace leaking heater and radiator hoses as required, para.  7-5. If leakage is not observed in steps a and b above, continue to pressurize system for five minutes and observe pressure gauge on cooling system pressurizer. If pressure remains constant after five minutes of pressurization, radiator and cooling system do not have leakage. If pressure lowers during five minutes of pressurization, internal coolin9 system leak in engine or transmission is present. Refer to Direct Support Maintenance. 5. AFTER TEST IS COMPLETED, REMOVE PRESSURIZER FROM RADIATOR FILLER NECK AND INSTALL RADIATOR CAP (4). 6. IF REMOVED FROM STORAGE POSITION, INSTALL THE LOAD BACKREST AT REAR OF VEHICLE . 7-13