TM 9-2815-225-34&P 3-63.  FUEL PUMP TESTING AND CALIBRATION (Contd) LOCATION/ITEM ACTION REMARKS l.  Calibration Check Points (Contd) 89. Front cover (53) and a.  Stop test stand (1) and remove Refer to para. 3-61 for removal. governor plunger (107) cover (53) and plunger (107). b.  Check torque spring (108) and Incorrect spring may have been shims (109). used or spring may be improperly seated or shimmed.  Install correct spring and shims as needed. Torque spring shims are available in 0.005, 0.010, and 0.020 in. (0.127, 0.254 and 0.508 mm) thickness.  If new torque spring or shims are installed, recalibrate pump. c.  Install cover (53) and plunger Refer to para. 3-61 for (107) and start test stand (1). installation. 90. Slow switch (23) Depress and release until pump Throttle lever (48) should still and fast button (25) speed is at 1000 rpm as be in full-throttle position. indicated on tachometer (7). 91. Flow control valve (37) Adjust until fuel flow through flowmeter glass tube (38) is exactly 300 pph as indicated by float in tube. 92. Fuel pressure gauge (2) Check fuel pressure reading. Proper reading should be (See Table 3-8 for Big Cam I between 73 and 81 psi (503 and fuel pump values only). 558 kPa) at 300 pph fuel flow.  If pressure reading is incorrect, do step 93.  If pressure reading is correct, go to step 94. 93. Front cover (53) and weight- a.  Stop test stand (1) by depress- Refer to para. 3-61 for removal. assist plunger (110) ing stop button (24) and remove front cover (53) and weight-assist plunger (110). b.  Add or remove shim (114) Add shims to increase pressure until correct fuel pressure and remove shims to decrease reading is obtained. pressure.  Shims are available in 0.007 and 0.015 in.  (0.177 and 0.381 mm) thickness. c.  Install front cover (53) and Refer to para. 3-61 for weight-assist plunger (110).  Start installation. test stand (1) by depressing start button (26) and repeat calibration beginning with step 54. 3-506