Cummins ISX11.9 CM2250 – Service Manual 001-008   Camshaft

This procedure requires that camshaft guide kit, Part Number 4919438, be used for proper installation and to prevent damage to the camshaft bushings in the cylinder block.

This procedure provides instructions on how to change the camshaft while the engine is still in the chassis and with the cylinder head installed. If the engine is removed from the chassis, removal of the flywheel housing should simplify the rear camshaft gear installation process.

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
• If required, remove the engine from the chassis. Refer to Procedure 000-001 in Section 0.
• If required, remove the radiator. Refer to the OEM service manual.
• Remove the cooling fan. Refer to Procedure 008-040 in Section 8.
• Remove the front gear cover. Refer to Procedure 001-031 in Section 1.
• Remove the front camshaft idler gear. Refer to Procedure 001-036 in Section 1.
• Remove the camshaft rear cover plate. Refer to Procedure 001-011 in Section 1.
• Remove the rocker lever cover. Refer to Procedure 003-011 in Section 3.
• Remove the push tubes. Refer to Procedure 004-014 in Section 14.
• Remove the electronic control module (ECM) for access to the camshaft timing boss. Refer to Procedure 019-031 in Section 19.

NOTE: It is possible to remove the camshaft without removing the cylinder head. The cam followers can be tied up and away from the camshaft with wire.

With the cylinder head installed, raise the cam follower assemblies. Use a wire to tie the cam followers up and away from the camshaft.

At the front of the engine, rotate the camshaft to align the holes in the front camshaft gear with the thrust plate capscrews.

Remove the thrust plate capscrews.

Rotate the engine to lock the crankshaft in place with the crankshaft locking pin, Part Number 2892115. Insert the pin in the hole in the crankshaft timing pin boss.

The colored band on the timing pin will be lined up with the surface of the timing pin boss of the block when seated correctly.

The pin is not correctly seated in the crankshaft notch if the colored band is either completely visible outside the block, or is not visible at all.

Remove the camshaft rear cover plate. Refer to Procedure 001-011 in Section 1.

Install three fully threaded, 3 inch long or greater, 1/2 inch UNC capscrews into the three bolt pattern shown.

Tighten the capscrews.

This will secure the rear camshaft gear into position while removing and installing the camshaft from the front of the engine.

Remove the five rear camshaft capscrews and clamping plate from the rear camshaft gear.

NOTE: The camshaft can now rotate separate of the camshaft gear.

Screw the stud adapters into the rear nose of the camshaft.

Place the camshaft guide onto the stud adapters as illustrated, without the wedge installed at this time. This will allow the guide to pass through the smaller bore  rear camshaft gear.

Thread the mounting capscrews through the camshaft guide and into the stud adapters.

From the front of the engine, rotate and pull the camshaft until the front of the second camshaft journal is flush with the front gear housing.

The camshaft guide should be past the rear camshaft gear.

To prevent forward movement of the camshaft during installation of the expanding wedge, temporarily install the L-shaped clamp to the front of the gear housing as illustrated.

Rotate the camshaft 180 degrees. The plastic guide must be downward.

Fully insert the expanding wedge into the assembly and secure with an Allen head screw. This is to prevent the wedge from falling into the oil pan during the removal of the camshaft.

Remove the L-shaped clamp from the front of the gear housing.

The plastic guide must be resting along the bottom of the camshaft bore.

Remove the camshaft  by pulling slightly, with minor  movement of the camshaft, to carefully work the camshaft through the camshaft bushings. As each camshaft journal passes through a bushing, the camshaft will drop slightly and the camshaft lobes will catch on the bushings.  Movement of  the camshaft will free the lobe from the bushing and allow the camshaft to be removed.

Remove the camshaft guide tool kit.

If necessary, unlock the crankshaft by removing the crankshaft locking pin, Part Number 2892115.

WARNING  When using a steam cleaner, wear safety glasses or a face shield, as well as protective clothing. Hot steam can cause serious personal injury.

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

Clean the camshaft with steam or solvent.

Dry with compressed air.

Measure the clearance between the gear hub and the thrust plate. Refer to Procedure 001-065 in Section 1.

Measure the outside diameter of the seven camshaft bushing journals.

Camshaft Bushing Journal Outside Diameter

Inspect the camshaft lobes for cracks, scratches, or other damage.

Refer to Camshaft Reuse Guidelines for Cummins® Engines with Roller Followers or Roller Tappets, Bulletin 3666052.

Remove the camshaft gear and measure the camshaft nose (1), thrust plate (2), and gear (3). Refer to Procedure 001-013 in Section 1.

Rotate the crankshaft clockwise until the ”Insert Pin” mark on the outside diameter of engine vibration damper is aligned with the slot, cut in the lower left of the front gear housing. Refer to Procedure 009-035 in Section 9.

Lock the crankshaft in place with the crankshaft locking pin, Part Number 2892115. Insert the pin in the hole in the crankshaft timing pin boss.

The colored band on the timing pin will be lined up with the surface of the timing pin boss of the block when seated correctly.

The pin is not correctly seated in the crank notch if the colored band is either completely visible outside the block, or is not visible at all.

Screw the stud adapters into the rear nose of the camshaft.

Place the camshaft guide onto the stud adapters as illustrated.

Thread the mounting capscrews through the camshaft guide and into the stud adapters

Fully insert the expanding wedge into the assembly and secure with an Allen head screw. This is to prevent the wedge from falling into the oil pan during installation of the camshaft.

Apply a liberal coating of lubricant, such as Lubriplate™ 105 or equivalent, to coat the camshaft bushings and camshaft.

CAUTION  Do not force the camshaft into the camshaft bore, as damage to the camshaft bushing can result.

NOTE: The sequence to this installation is very important. Read these instructions thoroughly before proceeding.

Start at the front of the engine. The plastic guide must be resting along the bottom of the camshaft bore.

Install the camshaft  by pushing slightly, with minor  movement of the camshaft, to carefully work the camshaft through the camshaft bushings. As each camshaft journal passes through a bushing, the camshaft will drop slightly and the camshaft lobes will catch on the bushings. Movement of  the camshaft will free the lobe from the bushing and allow the camshaft to be installed.

Stop installing the camshaft when the second camshaft journal is flush with the front gear housing.

Rotate the camshaft 180 degrees. The plastic guide should now be upward.

To prevent forward movement of the camshaft during removal of the expanding wedge, temporarily install the L-shaped clamp to the front of the gear housing as illustrated.

At the rear of the engine, remove the M6 Allen head capscrew that is securing the expanding wedge from the guide assembly.

There is a larger M8 thread, step machined into the M6 hole, for removing the wedge assembly. To remove the wedge assembly, thread a M8 capscrew into the wedge guide hole and pull out the wedge guide.

The camshaft guide will now insert into the same bore of the rear camshaft gear.

Remove the L-shaped clamp from the front of the gear housing.

CAUTION  Do not force the camshaft into the camshaft bore, as damage to the camshaft bushing can result.

NOTE: The sequence to this installation is very important. Read these instructions thoroughly before proceeding.

At the front of the engine, finish installing the camshaft by pushing slightly, with minor movement of the camshaft, to carefully work the camshaft guide through the rear camshaft gear bore and the remaining camshaft bushings.

Remove the camshaft guide tool kit.

NOTE: Be sure the camshaft is completely installed and engaged completely with the rear camshaft gear before the thrust plate is tightened. The thrust plate must not be used to drive the camshaft into place. Doing so can result in damage to the thrust plate.

Install the front camshaft gear if it has been removed. Refer to Procedure 001-012 in Section 1.

At the front of the engine, rotate the camshaft to align the holes in the camshaft gear with the thrust plate capscrew holes in the cylinder block.

Align the capscrew holes in the thrust plate with the cylinder block capscrew holes.

Install and tighten the capscrews.

Insert the timing pin, Part Number 4919342, in the hole in the camshaft timing pin boss.  Rotate the camshaft to find the slot in the camshaft and insert the timing pin.

The pin is not correctly seated in the camshaft notch if the green band is either completely visible outside the block, or is not visible at all.

Lock the camshaft in place with the camshaft locking pin, Part Number 4919342.

At the rear of the engine, remove the three 1/2 inch UNC capscrews from the flywheel housing that held the rear camshaft gear in position.

Apply pressure on the camshaft gear in a clockwise direction to take the lash out of the gear train.

Tighten the rear camshaft capscrews in a star pattern after timing the engine.

Unlock the camshaft by removing the camshaft locking pin, Part Number 4919342.

Unlock the crankshaft by removing the crankshaft locking pin, Part Number 2892115.

Measure the camshaft end clearance. Refer to Procedure 001-065 in Section 1.

Do not drop the cam follower levers on the camshaft lobes.

Carefully lower the cam followers onto the camshaft.

Use caution not to scratch or damage the rocker housing when removing the wire.

CAUTION  Failure to check the engine timing can cause severe engine damage.

Check the engine timing. Refer to Procedure 001-088 in Section 1.

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.

• Install the camshaft rear cover plate. Refer to Procedure 001-011 in Section 1.
• Install the front camshaft idler gear. Refer to Procedure 001-036 in Section 1.
• Install the push tubes. Refer to Procedure 004-014 in Section 14.
• Adjust the overhead. Refer to Procedure 003-004 in Section 3.
• Install the rocker lever cover. Refer to Procedure 003-011 in Section 3.
• Install the front gear cover. Refer to Procedure 001-031 in Section 1.
• Install the ECM. Refer to Procedure 019-031 in Section 19.
• If required, install the engine into the chassis. Refer to Procedure 000-002 in Section 0.
• Install the cooling fan. Refer to Procedure 008-040 in Section 8.
• If required, install the radiator. Refer to the OEM service manual.
• Connect the batteries. Refer to the OEM service manual.
• Operate the engine to normal operating temperature and check for leaks.