TM-9-2815-220-34 Direct Support Manual for AVDS-1790-2C and AVDS-1790-2D Engines Download

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I I TM 9-2815-220-34 P�dur e DT 3. Fuel Injection Pump Test.s DT 3.1 Pumping Action 1. Perform Test DT l.8 D 3.2 t. 2. Pump Rotation Remove top deck, engine rear cꝏling fan vane and rear fan. Crank engine. OT 4. Engine Fuel Return Tesl DT 4.1 Retu Fuel Flow I. Open rear grille dꝏ and remove transmission cover. Disconnect tank fuel return hose quick dis- connect coupling at rear or l rnnsmiion. 2. Hold quick disconnect coupling vake open lo collect fuel in suitable container. CAUTION Do not operate engine unles coupling valve is held open. 3. Start and operate engine at idle speed and collect fuel in con. tainer. 4. Remo\'e coupling half from fuel tank tube and onnecl coupling halves on he; operate engine (3. aho1•e): DT 5. Engine Fuel Shut-Off Operational Check OT 5.l Electric Control: l. Open top ille door,with Master Switch "ON'', intermittently operate fuel shutff switch "ON" and "OFF" (with manual control in normal engine "ON" posilion). 5.2 Manual ntrol: 1. With Master Switch "ON" h'old manual control handle in engine "OFF" position and intermH- lently operate electric fuel shut- off switch "ON" and "OFF". DT 6. DT 6.1 1. DT 6.2 l. Vehicle In-Tank Fuel Pump Operation Pump Operational check Open top grilles, Turn master +wilch "ON". Turn in-lank pump fuel stch "ON".- Pump Fuel Preurt: Perform Test DT 1.2. 2·26 Change 3 Table 2-3. Dinostic Tests - ntinued lli on a. High pressure fuel spray pulsations. a. Fuel injeclion pump shaft. b. Fuel injection pump shaft and/or coup- ling do not rotate. a. Moderate fuel flow from coupling valve {approx. p gpm). b. Trickle or no flow from he a. Moderate flow. b. Trickle or no flow. a. Note for audible solenoid "clicking" in- dicating opening and closing action. a. If no audible "cl! cking" is noted. b. Audible "clicking" is noted. a. �ectric pump operation audible (left and right fuel tanks). b. Pump {s) operation not audible. An1ly1is a. Spray pulsations indicate fuel injec- tion puniping action is salisfactory. No spray pulsations indicates a defective pump. a. b. Drive upling is satisfactory if coup- ling and pum p rotate. Fuel injection pump coupling failed or lꝏse on pump shaft. a. No restriction. Return fuel flow rat is satisfactory. b. Fuel flow is insufficient. Pinched or kinked line or quick disconnect coup- ling valve defective. a. Quick disconnect cou p l ing val ve satisfactory. b. Fuel tank return tu or he p inched or kinked, or quick disconnect coup- ling defective. al. Audible "clicking" indicates normal fuel shutff operation. a2. No audible "cli cking" indicates lenoid or circuit defective. a. Manual control is holding fuel shut-0ff in "OFF" position and manual operation is satisfactory. b. Manual control out of adjustment, or defective. a. Pup(s) is operative. b. Pump(s) i s inoperative.