Repair 7

How to Change a 6 5 Fuel Injector Pump

Many vehicles made by General Motors from 1992 to 2000 have a 6.5-liter engine with eight cylinders. These engines were most common in larger trucks like 3/4-ton and larger pickup trucks. The General Motors 6.5-liter engine uses fuel injection and almost always had a turbocharger. This requires a fuel injector pump to transfer the fuel from the fuel tank to the engine under high pressure.

Instructions

1

Disconnect the cable from the negative battery terminal with a socket wrench. Wrap a fuel fitting in a heavy shop towel and loosen the fitting to relieve the pressure in the fuel system. Tighten the fuel fitting.

2

Remove the intake-manifold with a socket wrench. Disconnect the fuel lines and the electrical wiring from the injection pump. Detach the fuel return line from the top of the injection pump. Plug the open fuel lines with clean cloth to keep debris out of the fuel system. Remove the oil filler and its grommet from the engine.

3

Turn the crankshaft clockwise by hand until the gear bolts for the injection pump are visible through the hole for the oil filler neck. Remove the gear bolts with a socket wrench and disconnect the nuts that attach the injection pump to its front cover. Remove the injection pump from the engine.

4

Align the pin on the hub of the new injection pump with the slot in the gear for the injection pump. Turn the crankshaft clockwise to align the timing marks on the torsional damper with the zero mark on the timing tab. Connect the fuel injection pump to its front cover with a socket wrench. Tighten the nuts for the front cover to 30 foot-pounds of torque with a torque wrench.

5

Fasten the bolts that attach the injection pump to its driven gear and tighten them to 20 foot-pounds of torque with a torque wrench. Install the oil fill tube and its grommet. Connect the bracket for the air conditioner with a socket wrench. Remove the plugs from the fuel lines, and connect the fuel feed line to the injector pump. Tighten the retaining bolts for the fuel line to 20 foot-pounds of torque with a torque wrench.

6

Connect the fuel return line and electrical wiring to the injector pump. Replace the intake-manifold with a socket wrench and attach the cable for the negative battery terminal. Start the engine and correct any fuel leaks.