TM-9-2815-210-34-2-1 LDS-465-1/LDS-465-2 Multifuel Engine Maintenance Manual Part 1
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TM 9-2815-210-34-2-1 b. Run the engine at low idle speed (5 minutes minimum for fuel mixing) until water temperature reaches 120°F. Higher water temperatures are acceptable. How- ever, the misfiring described below may go away as the engine reaches operating temperature. c. With engine at idle speed and transmission in neutral, attempt to accelerate to rated engine speed. Rated engine speed is 2,600 rpm for all models except LDS-465-2 (M656 Series Trucks), which is 2,800 rpm. Smooth, rapid acceleration to rated speed without misfire shows that fuel is good as is. If this condition is not met, addition of diesel fuel is required (up to 30 percent diesel fuel may be necessary). NOTE Misfire at higher than rated engine speed is good while performing the above test. d. Other reasons for the addition of diesel fuel that may happen during normal operation are: (1) Not being able to accelerate a warm ( 120°F. minimum water temperature) engine under light loads. (2) Popping in the exhaust system when accelerating after going down a long down grade. (3) Popping in the exhaust system when shifting transmission. NOTE Vehicles wit h two tank fuel systems: If unknown, or low octane fuel is added to both tanks, the secondary tank must have the same amount of diesel fuel added to the primary tank plus an additional 10 gallons of diesel fuel. 1-17/(1-18 blank)