Cummins ISX11.9 CM2250 – Service Manual 009-016   Hydraulic Pump Drive

Hydraulic pumps are driven by the engine’s gear train through the use of the hydraulic drive adapters. There are typically two hydraulic drives used on the ISX11.9 engine. They are:

1. Engine mounted hydraulic drive adapter
2. Air compressor mounted hydraulic drive adapter.

Air Compressor Mounted Hydraulic Drive Adapter

• The most common hydraulic pump used in this location is a power steering pump. The OEM is typically responsible for installing the power steering pump, including selecting the pump’s manufacturer and size for the vehicle. Refer to the OEM service manual for installation instructions.  Use the following procedure for air compressor installation and inspection instructions. Refer to Procedure 012-014 in Section 12.

Engine Mounted Hydraulic Drive Adapter

• The ISX11.9 hydraulic drive adapter is mounted on the front gear housing. This procedure describes the installation and inspection instructions for the hydraulic drive adapter. The OEM is typically responsible for installing the hydraulic pump, including selecting the purpose, manufacturer, and size of the hydraulic pump for the vehicle.  Refer to the OEM service manual for installation instructions.

NOTE: This step is for an air compressor mounted hydraulic pump.

• Disconnect all hydraulic lines from the pump. Refer to the OEM service manual.
• Remove the hydraulic pump and gear assembly. Refer to the OEM service manual.

NOTE: This step is for an engine mounted hydraulic drive adapter.

• Disconnect all hydraulic lines from the pump. Refer to the OEM service manual.
• Remove the two mounting capscrews and the hydraulic pump, if equipped, or the cover plate. Refer to the OEM service manual for hydraulic pump removal instructions.

Remove the three pump drive mounting capscrews.

Install a slide hammer and the engine baring tool, Part Number 3824270, to the hydraulic drive adapter. Use two M10-1.50 x 30 capscrews, Part Number 3335003, for SAE `A’ drives, or two M12-1.75 x 40 capscrews, Part Number 3018671, for SAE `B’ drives.

CAUTION  Do not allow the hydraulic drive gear to slide out of the adapter or the gear housing during removal. Damage to the gear will result.

Remove the hydraulic drive adapter, o-ring, thrust bearings, and hydraulic drive gear.

NOTE: The needle bearings should only be removed when they are damaged and/or being replaced.

If necessary, use the expanding bearing removal tool included in the bearing puller kit, Part Number 4919740, or equivalent, to remove the needle bearing from the gear housing.

NOTE: The needle bearings should only be removed when they are damaged and/or being replaced.

If necessary, use bearing removal tool, Part Number 3823776, included in the bearing puller kit, Part Number 4919740, or equivalent, to remove the needle bearing from the hydraulic pump adapter.

If applicable, remove the gasket material from the hydraulic pump and hydraulic adapter or air compressor or cover plate surface.

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 hydraulic pump adapter, thrust bearings, cover plate, gear and shaft assembly, and needle bearings with solvent.

Dry with compressed air.

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.

If the needle bearing was removed, clean the needle bearing bore in the gear housing with solvent and dry with a clean cloth.

Inspect the components for damage.

If the needle bearing was removed, measure the inside diameter of the needle bearing bore in the gear housing.

Needle Bearing Bore Inside Diameter (Gear Housing)

If the needle bearing was removed, measure the inside diameter of the needle bearing bore in the hydraulic pump drive adapter.

Needle Bearing Bore Inside Diameter (Hydraulic Pump Drive Adapter)

Measure the thrust washer thickness in three places, 120-degrees apart, between the oil grooves.

Camshaft Idler Thrust Washer Thickness

Flex the thrust washers approximately 3 to 6 mm [1/8 to 1/4 in], and inspect the surfaces for cracks.

Measure the hydraulic drive shaft outside diameter.

Hydraulic Drive Shaft Outside Diameter

NOTE: This section is for engine mounted hydraulic drive adapters.

If the needle bearings were removed, use clean 15W-40 oil to lubricate the outside diameter of the needle bearings and the needle bearing bores in the gear housing and the hydraulic pump drive adapter.

If the needle bearing was removed, use bearing installation tool, Part Number 4919762, included in the bearing puller kit, Part Number 4919740, to install the needle bearings in the gear housing.

Tap the bearing gently until it comes in contact with the shoulder in the housing.

The bearing must be 0.25 to 0.76 mm [0.010 to 0.030 in] past the outside edge of the gear housing bore surface.

If the needle bearing was removed, use bearing installation tool, Part Number 4919762, included in the bearing puller kit, Part Number 4919740, to install the needle bearing in the hydraulic pump drive adapter.

Install the needle bearing in the hydraulic pump drive adapter from the inside end (the end that will be closest to the hydraulic drive gear).

The bearing is to be pressed in until it is flush or within 0.5 mm [0.02 in] of the stop surface.

Use Lubriplate™ 105, or equivalent, to lubricate the needle bearing in the gear housing and the outside of the hydraulic driveshaft.

Install a thrust bearing on the hydraulic drive shaft on either side of the gear.

NOTE: The thrust bearings are non-directional

Install the shaft and gear assembly so the internal splines of the shaft are facing away from the gear housing and toward the rear of the engine.

Install a new o-ring on the hydraulic drive adapter. Lubricate the o-ring with clean 15W-40 oil.

Lubricate the hydraulic drive adapter needle bearing and bore with Lubriplate™ 105 or equivalent.

Install the hydraulic drive adapter over the shaft and gear assembly.

NOTE: The bearing should be installed toward the gear.

Start the three mounting capscrews by hand to align the hydraulic drive adapter with the gear housing.

Use a rubber hammer to tap around the outside diameter of the adapter to install the adapter.

NOTE: Use care not to damage the o-ring during installation.

Tighten the mounting capscrews.

Measure the driveshaft end clearance.

Use dial indicator assembly, Part Number 3376050, with extension, Part Number ST-537-4, and a magnetic base, Part Number 3377399.

Hydraulic Pump Driveshaft End Clearance

Use a new gasket and install the hydraulic pump cover plate, if equipped.

Install the two mounting capscrews and tighten.

If equipped with a hydraulic pump, install the gasket, hydraulic pump, and mounting bracket(s). Refer to the OEM service manual for torque specifications and installation instructions.

NOTE: This section applies to air compressor mounted hydraulic drive adapters.

Use a new gasket and install the hydraulic pump.  Refer to the OEM service manual for installation instructions and torque specifications.

• Connect all hydraulic lines to the pump. Refer to the OEM service manual.
• Operate the engine and check for leaks and proper operation.