TM-9-2320-387-24 HMMWV Direct Support & General Support Maintenance Manual Volume 1 Download
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REFERENCE INFORMATION FUEL SYSTEM You should only run the engine lpng enough to determine the gauge reading because engine temperature must stay below 90° F (33O C) for the cold-advance circuit to function. BATTERY VOLTAGE MULTlMElER I. Set the voltmeter to a DC volts scale of at least 40 volts. 2. Connect the RED lead to positive and the BLACK lead to negative. 3. Be sure to read the correct scale. DC VOLTAGE 9-45 VOLTS STUICE-R TEST 89 1. Connect RED clip to positive. BLACK dip to negative or ground. 2. Start Test 99, DC volts. 3. Displayed reading is in volts. 1. 2. 3. 4. Shut off engine. Disconnect wire 569 at cotd- advance switch. Turn rotary switch to RUN oosition. ‘Check for battery 569. voltage at wire Repair/replace harness (para. 4-90). NOTE Engine temperature must be less than WF (330 C) when testing the switch. Replace cold-adavance swftch (para. 4-31). Repair/replace harness (para. 4-30). TM 9-2320-387-24-l . COLD-ADVANCE CIRCLET FROM PROTECTWE CONTROL BOX I Alternator output is hot when the rotary switch is in the RUNposition. Cold-advance switch is closed when engine temperature is below 90°F (33°C) and open when it goes above 120°F (49%). The cold-advance solenoid advances the injection pump timing when it receives power from the switch. This helps the engine run better when it is cold. 2-l 35