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 rnnsmiion. 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 he; 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 shutff 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 stch "ON".- Pump Fuel Preurt: Perform Test DT 1.2. 2·26 Change 3 Table 2-3. Dinostic 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 he 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 he p inched or kinked, or quick disconnect coup- ling defective. al. Audible "clicking" indicates normal fuel shutff 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. Pup(s) is operative. b. Pump(s) i s inoperative.