TM 9-2910-226-34 plunger sleeve toward increased fuel delivery. The engine then increases to original speed. - f. If engine load is decreased, the speed will momentarily increase and the governor weights will move further out. The fingers on the weights shift the sliding sleeve against the opposing spring forces. The fulcrum lever shifts and moves the plunger sleeve toward decreased fuel delivery, reducing engine speed. g. The operating shaft is connected to the fulcrum lever by the shaft spring plate (C) and operating shaft spring (D). The fork on the upper portion of the shaft spring plate engages the fulcrum lever. The operating shaft spring grips the tang on the spring plate and the tang on the operating shaft. This torsion spring loads both tangs toward each other so that normally the operating lever and fulcrum lever act as though rigidly attached. When engine speed differs as a result of load changes, from the normal to the operating lever position, the tangs part momentarily until the governor senses the change. This function protects - the governor and fuel in- jection pump parts from unnecessary high loads and stresses. NOTE The key letters shown below in parentheses refer to figure 1-18. The functioning of the torque link assembly applies only to code A-injection pumps. As the torque link (D) moves upward, the fuel stop wedge (F) moves upward to an increased fuel delivery. ‘As it moves downward the fuel delivery decreases. h. The principle function of the torque link assembly is to control the sliding stop wedge (F) and its movement up and down. Due to its wedge con- figuration, as it moves up it moves the stop plate (H) forward allowing the smoke limit cam (G) to move to an increased fuel position. As it moves downward it moves the stop plate toward the rear of governor housing or a decreased fuel position. The torque link assembly limits maximum fuel quantity at any position of the operating shaft assembly other than the full-load position or low-idle position of the operating shaft assembly. i. When the operating shaft assembly is in the full-load position the torque link assembly is in the full-load quantity position. Pin (K) has contacted surface (L) of kidney slot and raised the torque link assembly to its maximum upward travel position. As the operating shaft assembly is moved away from the full-load position the torque link assembly moves downward resulting in decreased fuel. At an in- termediate operating shaft position, the spring (C) moves stop wedge (F) downward to a position where both pins - come in contact with the torque link assembly. This position represents maximum fuel limiting effect. In the low-idle position, pin (N) has contacted surface (P), and raised the torque link assembly. This provides maximum fuel delivery for engine starting. The purpose of above operations is to protect the engine and automatic transmission from excessive load changes during shifting, while maintaining power at full load and providing suf- ficient starting fuel quantities. 1-26. Timing Advancement. NOTE The key letters shown below in parentheses refer to figure 1-16. As the engine speed rotates the weight and spider assembly (AH), centrifugal force opens the flyweights from. their collapsed position. The loading of the three timing device springs (B) acts against the flyweights until a certain engine speed is reached, at which point the forces of springs and flyweights are balanced. As engine speed increases, the flyweights swing out and force the sliding gear (A) toward the timing device hub (C). As a result of this longitudinal and axial movement of the sliding gear, the metering and distributing pump camshaft is rotated slightly out of phase and in advance of the weight and spider. The axial movement of the sliding gear is caused by the internal helical splines of the sliding gear acting on the external helical splines of the weight and spider and the timing device hub (para 1-16). Therefore, the timing of the fuel pump with relation to the top dead center position of the engine’s piston is advanced within a given range. 1-27. Fuel Density Compensating (Typical). a. The multifuel engine operates on fuels having a significant variation in density and heat value per gallon. These variations in the fuels affect engine output. Any power loss due to a change of fuel is not acceptable. The fuel density compensator on the fuel injection pump automatically varies the quantity of fuel delivered to the engine to maintain a constant maximum power output regardless of the fuel being used. b. The characteristics of the fuels used in the en- gine show a definite relationship between viscosity and heating value. The fuel density compensator takes this into consideration by making the viscosity characteristic a sensed variable. In the compensator the fuel is passed in series through two orificies of widely different flow characterist its. A change in viscosity of the fuel flowing through these orifices causes a pressure drop change which moves a servo diaphragm (fig. 1-28) or piston (fig. 1-29) to vary the full-load stop of the fuel injection pump. 1-29