How to Install a VP44 Pump

The VP44 fuel injection pump enhances electronic rotary distribution. The VP44 pump produces high fuel pressure, meters precise fuel amount, distributes fuel to each cylinder and delivers fuel at exact time intervals during the injection process. The injector pump's design consists of a three-pronged cam ring, rotor and electrical solenoid valve that develops and distributes the high pressure needed during the injection process. Damaged internal components greatly affect the pressure and the amount injected into the engine. VP44 pump installation requires an adequate mechanical background.

Things You'll Need

  • Safety goggles
  • Helmet
  • Gloves
  • Steel-toed shoes
  • Clean rag
  • Vacuum gauge
  • Metric ratchet set: 10 to 27 mm
  • T-bar, 75 mm
  • Brake cleaner
  • Mounting screws
  • Cap screws
  • Disconnect the pump's drain line from the t-fitting and plug it with a clean rag. Dislodge the vacuum hose from the drain line. Connect the vacuum hose to the pump's inlet line and allow the fuel to travel back into the fuel tank.

  • Use the vacuum gauge to test the fuel system. The vacuum test must result in 381 to 508 mm Hg. If the gauge reading does not drop more than 2.54 mm, then no leak exists in the fuel system. Check for leaks if the fuel system does not hold more than 2.54 mm.

  • Remove the battery terminal cables, starting with the negative connection. Remove the fuel pump access cap and bar the engine with the keyhole angled at the 12 o'clock position.

  • Disconnect the fuel return and fuel pump supply lines with a 17-mm ratchet. Dislodge the high-pressure lines with a 19-mm ratchet. Loosen and remove the nine-pin electrical connector from the pump's control panel.

  • Loosen and remove the fuel pump bracket bolts with a 10-mm ratchet. Dislodge the crankcase breather gear, nut and washer with an 27-mm ratchet. Use a 75-mm T-bar to slacken the pump drive gear from the pump's drift shaft. Slacken the four mounting bolts with a 13-mm ratchet and carefully pull out the fuel injection pump.

  • Clean the fuel pump gear housing, mounting surface and fuel injector pump housing of excess oil, grease and grime with a dry, unsoiled rag. Apply brake cleaner to the pump's shaft and gear bore.

  • Rotate the pump shaft for proper keyhole alignment. Place the VP44 pump into the gear housing by aligning the pump's mounting flange with the dowel located on the gear housing's rear. Do not allow the gear key to fall into the housing. Avoid the pump's mounting o-ring. Thread the mounting screws and hand tighten.

  • Insert the pump's drive shaft bolt and washer. Torque to 30 foot-pounds with a 24-mm ratchet. Install the pump's mounting bolts. Torque to 32 foot-pounds with a 15-mm ratchet.

  • Position the pump's bracket. Thread and hand-tighten the cap screw through the pump bracket and through the fuel pump. Insert and hand-tighten the pump brace to block cap screws. Install and finger-tighten the pump bracket cap screws through the fuel pump brace. Use a 10-mm ratchet to torque all cap screws to 212 inch-pounds. Tighten the pump's drift shaft nut with a 22-mm ratchet and a torque value of 125 foot-pounds.

  • Insert the crankcase breather. Connect the low-pressure, inlet and fuel return lines with a 17-mm ratchet. Use a 19-mm ratchet to install a high-pressure line at the fuel pump and cylinder head. Attach the nine-pin connector to the fuel injector pump. Connect the battery terminal cables, starting with the positive connector. Vent air from the fuel system.