SCREW-STRAGE BOX TO CLOSEOUT PANEL 6V8969 - Caterpillar

Fuel Transfer Pump
When the engine is operating at full load speed, the fuel transfer pump receives fuel from the primary fuel filter. Fuel flows through the ECM (if equipped) and flows through the secondary fuel filters to the fuel injection pump.Use the following steps to check the fuel transfer pump pressure.
Disconnect the fuel line from the filter at the fuel injection pump housing inlet.
Install a tee at the inlet.
Connect the fuel line to the tee.
Connect a pressure gauge to the tee.
Start the engine.
Fuel is delivered to the fuel pump housing at approximately 414 kPa (60 psi) at full load speed.If the fuel pressure is not to specifications, stop the engine. Replace the primary fuel filter and replace the secondary fuel filters. Make sure that the fuel lines and the hoses are not plugged or damaged.Start the engine and check the fuel pressure. If the fuel pressure is not at specifications, repair the fuel transfer pump or replace the fuel transfer pump.Checking Engine Cylinders Separately
If any of the following conditions occur, check the individual engine cylinders:
rough idle or rough operation
misfire
excessive black smokeUse this procedure to check the engine cylinders separately:
Run the engine at the roughest speed.
Loosen the fuel line nut at a fuel injection pump. This will stop the flow of fuel to that engine cylinder.After you shut off an engine cylinder's fuel flow, the engine should run more roughly.
Tighten the fuel line nut.
Repeat this maneuver with each engine cylinder in sequence until you discover a loosened fuel line that does not affect the engine's performance.
When you find the engine cylinder that does not affect the engine's performance, perform the following operations:
Test the fuel injection pump.
Test the fuel injection valve.When an engine runs at low idle rpm, the temperature of an exhaust manifold can also indicate the condition of a fuel injection valve. A low temperature indicates that no fuel is reaching the cylinder. This can possibly signify that the fuel injection valve has a defect.When an engine runs at low idle rpm and the temperature of an exhaust manifold is at an extra high temperature, too much fuel is probably flowing into the engine cylinder. This can also signify that the fuel injection valve has a defect.The most common defects on fuel injection valves include the following defects:
carbon on the tip of a nozzle
carbon in the nozzle orifice
orifice wear
dirty nozzle screen