Cummins ISX11.9 CM2250 – Service Manual 002-001   Crosshead

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

• Disconnect the batteries. Refer to the OEM service manual.
• Remove the crankcase breather. Refer to Procedure 003-001 in Section 3.
• Remove the rocker lever cover. Refer to Procedure 003-011 in Section 3.
• Remove the engine brake assembly, if equipped. Refer to Procedure 020-024 in Section 20.
• Remove the push rods or tubes. Refer to Procedure 004-014 in Section 4.
• If necessary, remove the rocker lever assembly. Refer to Procedure 003-009 in Section 3.

NOTE: Make note of the crosshead location and orientation. If the crossheads are reused, they must be installed in their original location and orientation.

Remove the crossheads.

WARNING  When using solvents, acids, or alkaline materials for cleaning, follow the manufacturer’s recommendations for use. Wear goggles and protective clothing to reduce the possibility of personal injury.

WARNING  Some solvents are flammable and toxic. Read the manufacturer’s instructions before using.

WARNING  Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury.

Clean the crossheads with solvent.

Dry with compressed air.

Inspect the crossheads for cracks and/or excessive wear on the rocker lever and valve tip mating surfaces.

Inspect the rocker lever contact pad for wear, cracks, or other damage.

Wear in the pad contact area must not exceed 7 mm [0.276 in] width.

Dry with compressed air.

Measure the valve stem pocket depth from the valve stem pocket to the rocker pad face.

Stem Pocket to Pad Face

Use the magnetic particle residual method to inspect the crossheads for cracks.

Magnetize the crosshead in a coil of 100 to 200 amperes and inspect it with residual Magnaglo™.

Cracks will be indicated by a bright line. The primary location for cracks is the valve stem pocket area.

If cracks are found, the crosshead must be replaced.

WARNING  When using solvents, acids, or alkaline materials for cleaning, follow the manufacturer’s recommendations for use. Wear goggles and protective clothing to reduce the possibility of personal injury.

WARNING  Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury.

Remove all magnetism.

Clean the crossheads with solvent.

Dry with compressed air.

NOTE: The crosshead has a round hole and an oval hole. If installing new crossheads, it is not required to place the holes in a particular position.

NOTE: When reusing the crossheads, make sure to install the crossheads in their original location and orientation.

Install the crossheads on the valve stems.

When installing the crossheads on engines equipped with engine brakes, the pin on the crosshead should be facing the air intake side of the cylinder head.

Check to make sure the crossheads are seated properly on the valve stems by one or both of the methods below.

• Wiggle the crossheads sideways to make sure they are seated properly on the valve stems.  There should be a small amount of motion, but no major motion or sliding off the valve stems.
• Visually check the adjusting screws on each of the rocker levers.  There should be a similar number of threads exposed above the adjusting screws on each rocker lever.  If there are significantly more or less threads exposed on any of the rocker levers when compared to the rest, one of the crossheads may not be seated properly on the valve stem.

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

• If removed, install the rocker lever assembly. Refer to Procedure 003-009 in Section 3.
• Install the push rods or tubes. Refer to Procedure 004-014 in Section 4.
• Adjust the overhead. Refer to Procedure 003-004 in Section 3.
• Install the engine brake assembly, if equipped. Refer to Procedure 020-024 in Section 20.
• Install the rocker lever cover. Refer to Procedure 003-011 in Section 3.
• Install the crankcase breather. Refer to Procedure 003-001 in Section 3.
• Connect the batteries. Refer to the OEM service manual.
• Operate the engine to normal operating temperature and check for leaks.