Fuel System - Operation and Tests/In-line Injection Pump CTM3274 (01JUL99) 220-18 Saran Liter Engines 060799 PN=357 FUEL TRANSFER PUMP OPERATION (IN-LINE INJECTION PUMP) - CONT’D -UN-06AUG91 RG5787 A—Camshaft E—Plunger Spring I—Suction Valve M—Intermediate Stroke B—Roller Tappet F—Suction Chamber J—Fuel Inlet Position C—Pressure Spindle G—Pressure Valve K—Hand Primer Pump N—Suction and Discharge D—Plunger H—Pressure Chamber L—Fuel Outlet Stroke Position As the pump camshaft (A) rotates toward the “high Movement of the plunger pushes the fuel from the cam” intermediate stroke position (M), the roller pressure chamber and delivers it to the fuel filters tappet (B) and pressure spindle (C) cause the and injection pump.
At the same time, plunger suction plunger (D) to compress the plunger spring (E). pressure is permitting fuel to enter the suction chamber through the suction valve (I). With the Plunger movement forces the fuel out of the suction suction chamber charged with fuel, the pumping cycle chamber (F), through the pressure valve (G) and into begins again. the pressure chamber (H). The amount of fuel discharged from the suction chamber is equal to the Fuel is allowed to flow in around the pressure spindle amount of fuel delivered for each stroke of the to lubricate the spindle as it moves back and forth in plunger. Towards the end of the intermediate stroke, housing.
To prevent the fuel from entering the pump the spring-loaded pressure valve closes again. camshaft case, a rubber seal is positioned in the spindle bore of housing at the roller tappet end. As the camshaft rotates toward the “low cam” or suction and discharge position (N), plunger spring Unscrewing the knurled knob on the hand primer pressure causes the plunger, pressure spindle and pump (K) and pulling upward causes the suction roller tappet to follow the camshaft. valve to open and fuel to flow into the suction chamber. When the hand plunger is pushed downward, the suction valve closes and fuel is forced out of the pressure valve. CD,3274,G220,22-19-04JAN99 220 18