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Injection Pump Timing

  1. Turn crankshaft in direction of normal rotation until No. 1 cylinder is in compression stroke and 24° BTDC mark is aligned with pointer.
  2. Clean pump connections. Remove vacuum hoses from pump. Remove No. 1 injection line, then unscrew pipe connection and remove compression spring and pressure valve. Leave pressure valve carrier and copper gasket in place. See Fig 1 .
    CAUTION: Do not unscrew element connection below pipe connection or pump recalibration will be necessary.
    Fig 1: Injection Pump Pipe Connection Fittings
    G34664
    Fig 2: Checking Overflow Pipe Fuel Flow
    G34663
  3. Install pipe connection and overflow pipe. Rotate crank to 24° BTDC on compression stroke of first cylinder. Open vent or hollow screw on filter and use hand pump to pump fuel until it comes out of overflow pipe.
    NOTE: Place lever at full-throttle position while adjusting timing and checking overflow.
  4. Rotate crankshaft until fuel just stops dripping. One drop should fall about 3 seconds later. Note position on crankshaft pulley and adjust pump position so injection stops at 24° BTDC.
  5. Turn crankshaft 2 turns to check that fuel dripping stops with pump and crankshaft marks in correct position. Tighten pump bolts. Remove overflow pipe and install pressure valve, spring and pipe connection. Tighten fitting to 29-36 ft. lbs. (39-49 N.m) in one smooth motion.
  6. Install injection line and bleed fuel system. Run engine and check for leaks. If fitting leaks replace connection and gasket under pressure valve carrier.
Fig 3: Injection Pump Adjustment Locations
G34666