FUEL SYSTEM PRIMING

A certain amount of air becomes trapped in the fuel system when fuel system components on the supply and/or high-pressure side are serviced or replaced. Fuel system priming is accomplished using the electric fuel transfer (lift) pump.

Servicing or replacing fuel system components will not require fuel system priming. The fuel transfer (lift) pump is self-priming: When the key is first turned on (without cranking engine), the pump operates for approximately 1 to 2 second and then shuts off (Note: When ambient temperatures are cold enough to cause the intake air heaters to operate, the fuel lift pump will operate during the entire intake air pre-heat cycle). The pump will also operate for up to 25 seconds after the starter is quickly engaged, and then disengaged without allowing the engine to start. The pump shuts off immediately if the key is on and the engine stops running.

1. Turn the key to CRANK position and quickly release the key to ON position before engine starts. This will operate fuel transfer pump for approximately 25 seconds.

2. Crank engine. If the engine does not start after 25 seconds, turn the key to OFF position, and leave it off for at least 5 seconds. Repeat the previous step until the engine starts.
3. Fuel system priming is now completed.
4. Attempt to start the engine. If the engine will not start, proceed to following steps. When the engine does start, it may run erratically and be noisy for a few minutes. This is a normal condition.

CAUTION: Do not engage the starter motor for more than 30 seconds at a time. Allow two minutes between cranking intervals.
5. Perform previous fuel priming procedure steps using fuel transfer pump. Be sure fuel is present at the fuel tank.
6. Crank the engine for 30 seconds at a time to allow fuel system to prime.

WARNING: The fuel injection pump supplies extremely high fuel pressure to each individual injector through the high-pressure lines. Fuel under this amount of pressure can penetrate the skin and cause personal injury. Wear safety goggles and adequate protective clothing. Do not loosen fuel fittings while the engine is running.