Cummins ISX11.9 CM2250 – Service Manual 009-056   Alternator/Refrigerant Compressor Mounting Bracket

Most ISX11.9 engine configurations use a single mounting bracket to mount both the alternator and the refrigerant compressor.  Some configurations, however, use separate brackets for the alternator and refrigerant compressor.

Other ISX11.9 engine configurations use a modified alternator bracket to accommodate one or two alternators.

ISX11.9 engine configurations that use one or two alternators require a modified mounting bracket.  The mounting bracket for two alternators also requires an additional idler pulley and support bracket. Use the following procedure for more information on this bracket. Refer to Procedure 009-058 in Section 9.

ISX11.9 engine configurations that use a cold side mounted refrigerant compressor require a separate mounting bracket.  This bracket also serves as the mounting location for the refrigerant compressor belt tensioner. 

NOTE: Record the mounting location of the tensioner as there are two brackets that can be used. One provides a lower mounting point for the tensioner than the other.

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 cooling fan. Refer to Procedure 008-040 in Section 8.
• Remove the cooling fan drive belt. Refer to Procedure 008-002 in Section 8.
• Remove the refrigerant compressor drive belt. Refer to Procedure 009-052 in Section 9.
• Remove the cooling fan belt tensioner. Refer to Procedure 008-087 in Section 8.
• If equipped, remove the belt tensioner, automatic (refrigerant compressor). Refer to Procedure 009-053 in Section 9.
• If equipped, remove the dual alternator idler pulley support bracket.
• Remove the alternator. Refer to Procedure 013-001 in Section 13.
• Remove the refrigerant compressor. Refer to Procedure 009-051 in Section 9.

NOTE: This step is for the removal of the hot side alternator/refrigerant mounting bracket.

Remove the two capscrews that mount the alternator/refrigerant compressor mounting bracket to the front of the cylinder block.

Remove the four capscrews that mount the alternator/refrigerant compressor mounting bracket to the front right side of the cylinder block.

NOTE: Be sure to remove the refrigerant compressor belt tensioner to gain access to the mounting capscrews on the right side of the cylinder block.

NOTE: This step is for the removal of the refrigerant compressor mounting bracket.

Remove the two capscrews that mount the refrigerant compressor mounting bracket to the front of the cylinder block.

Remove the four capscrews that mount the refrigerant compressor mounting bracket to the front right side of the cylinder block.

NOTE: This step is for the hot side alternator/refrigerant compressor mounting bracket only.

Remove the idler pulley and capscrew from the alternator/refrigerant compressor mounting bracket.

NOTE: The alternator/refrigerant compressor mounting bracket uses a grooved idler pulley. The dual alternator mounting bracket uses a non-grooved idler pulley. Be sure the correct idler pulley is removed.

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.

Clean the parts with solvent.

Dry with compressed air.

Inspect the mounting brackets for cracks and fretting on the mounting faces.

Inspect the idler pulley capscrew holes for damage to threads.

Replace the pulley if it is damaged.

Inspect the spacer for any cracks or other damage.

Replace the spacer if it is cracked or otherwise damaged.

Inspect the grooved pulleys for cracks or broken grooves. Replace the idler pulley if it is damaged.

Spin the idler pulleys.

The idler pulleys must rotate freely when installed.

Inspect the non-grooved pulley for wear and damage.

Replace the idler pulley if it is damaged.

Spin the idler pulley.

The idler pulley must rotate freely when installed.

Replace the idler pulley if it is damaged.

NOTE: This step is for the hot side alternator/refrigerant compressor mounting bracket only.

Install the grooved refrigerant compressor idler pulley (1), dust shield, and mounting capscrew.

NOTE: The alternator/refrigerant compressor mounting bracket uses a grooved idler pulley. The dual alternator mounting bracket uses a non-grooved idler pulley. Be sure the correct idler pulley is installed.

NOTE: This step is for the hot side alternator/refrigerant mounting bracket.

Install the alternator/refrigerant compressor mounting bracket to the cylinder block.

NOTE: This is a two step process for proper installation of the alternator/refrigerant compressor mounting bracket.

Step 1:

• Install the M10 capscrews that mount the alternator/refrigerant compressor mounting bracket to the front right side of the cylinder block.

Step 2:

• Install the four remaining M12 capscrews.

NOTE: This step is for the refrigerant compressor mounting bracket.

Install the refrigerant compressor mounting bracket to the cylinder block.

NOTE: This is a two step process for proper installation of the refrigerant compressor mounting bracket.

Step 1:

• Install the three capscrews that mount the refrigerant compressor mounting bracket to the front left side of the cylinder block.

Step 2:

• Install the two capscrews that mount the refrigerant compressor mounting bracket to the front of the cylinder block.

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 refrigerant compressor. Refer to Procedure 009-051 in Section 9.
• Install the alternator. Refer to Procedure 013-001 in Section 13.
• If equipped, install the dual alternator idler pulley support bracket.
• If equipped, install the belt tensioner, automatic (refrigerant compressor). Refer to Procedure 009-053 in Section 9.
• Install the cooling fan belt tensioner. Refer to Procedure 008-087 in Section 8.
• Install the refrigerant compressor drive belt. Refer to Procedure 009-052 in Section 9.
• Install the cooling fan drive belt. Refer to Procedure 008-002 in Section 8.
• Install the cooling fan. Refer to Procedure 008-040 in Section 8.
• Connect the batteries. Refer to the OEM service manual.
• Operate the engine and check for proper operation.