F15158 Mercury SCREW

Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Cat Dealer Service Tool Catalog" or refer to Special Publication, PECJ0003, "Cat Shop Supplies and Tools Catalog" for tools and supplies suitable to collect and contain fluids on Cat products.Dispose of all fluids according to local regulations and mandates.
Do not allow dirt to enter the fuel system. Thoroughly clean the area around a fuel system component that will be disconnected. Fit a suitable cover over disconnected fuel system component.
Do not crank the engine for more than 30 seconds. Allow the starting motor to cool for two minutes before cranking again.
Illustration 1 g01568053
C11 and C13 On-highway Engines
(1) Fuel priming pump
(2) Air purge screw
(3) Priming valve (If equipped)
Illustration 2 g01568054
C15 On-highway Engines
(1) Fuel priming pump
(2) Air purge screw
(3) Priming valve (If equipped) The engine may need to be primed in the following circumstances:
The engine runs out of fuel.
The secondary fuel filter is replaced.If the engine runs out of fuel, take the following steps before you prime the engine:
Turn the ignition to the OFF position.
Fill the fuel tank with clean diesel fuel. Note: Refer to Operation and Maintenance Manual, "Fuel System Secondary Filter - Replace" for information on replacing the filter.Using the Engine to Prime the Fuel System
Turn the ignition switch to the OFF position.
Unlock the fuel priming pump (if equipped) by turning the cap counterclockwise.
Purging air from the fuel system requires the air purge screw to be opened. Turn the air purge screw counterclockwise by three full turns. Do not remove the screw.
Turn the ignition switch to the ON position.
Crank the engine for 30 seconds. Use a suitable container to catch the fuel while you crank the engine. Allow the starting motor to cool for two minutes. Note: Most of the air should be purged from the system after four or five cranking cycles.
Repeat Step 5 until the engine starts and runs. If the engine runs rough, continue to operate the engine at low idle until the engine runs smoothly.
Observe the air purge screw. When a small drop of fuel appears at the threads of the air purge screw, close the air purge screw. After the air purge screw is closed, tighten the air purge screw. Refer to Specifications, SENR3130 for the correct torque. Note: Failure to tighten the screw could result in serious fuel leaks.
After the engine has operated smoothly for 30 seconds, turn the priming valve to the LOCK position. Note: The life of the injectors may be shortened if the priming valve is left in the unlocked position.
Clean any residual fuel from the engine components.
Once the engine runs smoothly, stop the engine. Turn the ignition switch to the OFF position. Using the Fuel Priming Pump (If Equipped) to Prime the Fuel System
Turn the ignition to the OFF position.
Unlock the priming pump by turning the cap counterclockwise.
Purging air from the fuel system requires the air purge screw to be opened three full turns. Open the air purge screw. Do not remove the screw.
Continue to operate the fuel priming pump until a strong resistance is felt. Listen for an audible click from the fuel manifold. The click will indicate that the valve has opened and the fuel system is pressurized. Lock the fuel priming pump. Note: The life of the injectors may be shortened if the priming valve is left in the unlocked position.
Turn the ignition to the ON position.
Crank the engine. If the engine starts but the engine runs rough, continue to operate the engine at low idle until the engine runs smoothly. Note: If the engine will not start, further priming is necessary. If the engine starts but the engine continues to misfire, further priming is necessary.
Observe the air purge screw. When a small drop of fuel appears at the threads of the air purge screw, close the air purge screw. After the air purge screw is closed, tighten the air purge screw. Refer to Specifications, SENR3130 for the correct torque. Note: Failure to tighten the screw could result in serious fuel leaks.
Clean any residual fuel from the engine components.
Once the engine runs smoothly, stop the engine. Turn the ignition switch to the OFF position.