Centinel System – Repair Manual – 007-031   Lubricating Oil Pump

WARNING  To reduce the possibility of personal injury, avoid direct contact of hot oil with your skin.

WARNING  Some state and federal agencies have determined that used engine oil can be carcinogenic and cause reproductive toxicity. Avoid inhalation of vapors, ingestion and prolonged contact with used engine oil. If not reused, dispose of in accordance with local environmental regulations.

• Drain the lubricating oil. Refer to Procedure 007-037 in Section 7.
• Remove the lubricating oil pan. Refer to Procedure 007-025 in Section 7.
• Remove the lubricating oil suction tube. Refer to Procedure 007-035 in Section 7.

CAUTION  Do not discard shims, if equipped. They must be installed in the original location. Failure to do so can result in engine damage.

Remove four capscrews, oil pump, and shims if equipped.

When installing a new oil pump, new shims will possibly be needed to acquire acceptable lash.

WARNING  The pressure regulator spring is under compression. Slowly remove the cap to reduce the possibility of personal injury.

Remove the lubricating oil pressure regulator and spring by removing the split pin that secures the spring cap to the lubricating oil pump.

Discard the o-ring.

The external idler gear retaining capscrew has a left-hand thread. capscrew.

Remove the external idler gear from the lubricating oil pump.

Save the retaining capscrew for reuse.

WARNING  The high pressure relief valve is under compression. Apply pressure to the cover while removing the capscrews. Slowly release the pressure to reduce the possibility of personal injury.

Remove the six assembly capscrews and the lube pump cover.

Press off the external drive gear from the internal drive gear shaft.

Remove the high-pressure relief spring and ball.

Remove the idler pumping gear from the shaft in the lubricating oil pump body.

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.

CAUTION  Do not allow dirt or gasket material to enter the oil passages. Bearing damage can result.

Clean the lubricating oil pump components with solvent.

Use a bristle brush to clean any internal ports.

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.

Use a steam cleaner to rinse the components.

Dry with compressed air.

Inspect the following areas of the lubricating oil pump for damage or blockage.

• Lubricating oil pump body gear cavity
• Inlet and outlet ports
• Internal oil passages
• Lubricating oil pump housing body
• Pressure regulator bore
• High pressure relief bore and seat.

If the lubricating pump housing is damaged, it must be replaced.

Inspect the lubricating oil pump cover for damage.

Inspect the bushing for scuffing and wear.

If the marks on the lubricating pump cover can be felt with a fingernail, the part must be replaced.

Measure the regulator bore for beat-in.

Regulator Bore Depth Specification

If the regulator bore depth is not within the specifications, the housing must be replaced.

Inspect the pressure regulator spool for scuffing.

Minor spool scuff is acceptable. If the scuff can be felt by a fingernail, the spool will need to be replaced.

Insert the spool in the bore and check for smooth movement in and out of the bore. If any hesitation is felt, the spool must be replaced and the bore inspected for burrs.

Remove any burrs found in the bore before installing a new spool.

Inspect the pressure regulator spring for a broken coil or rust.

Measure the free length of the pressure regulator spring.

Oil Pressure Regulator Spring Free Length

Use a spring compression tester, Part Number 3375182, to measure the pressure regulator valve spring at working height, 70 mm [2.756 in].

Lubricating Oil Pressure Regulator Spring Load at 70 mm [2.756 in]

If the regulator spring is not within the specifications, the spring must be replaced.

Inspect the high pressure relief spring for a broken coil or rust.

Measure the free length of the high pressure relief spring.

High Pressure Relief Valve Spring Free Length

Use a spring compression tester, Part Number 3375182, to measure the high pressure relief spring at working height, 45.82 mm [1.804 in].

High Pressure Relief Valve Spring (Compressed Length) Load at 45.82 mm [1.804 in]

If the pressure relief valve spring is not within the specification, the spring must be replaced.

Inspect the high pressure relief ball. A slight ring around the ball from contact with the pump body and spring is acceptable.

Inspect the external idler gear retainer.

Minor retainer scuff is acceptable. If the scuff can be felt by a fingernail, replace the retainer.

Inspect the external idler gear for cracks, chips, and broken teeth.

If the external idler gear is damaged, the gear must be replaced.

Check the idler gear bushing for wear and scuffing.

Measure the inside diameter of the bushing in the external idler gear.

External Idler Gear Bushing Inside Diameter

If the external idler gear bushing is not within specifications, the bushing must be replaced.

Inspect the external drive gear for cracks, chips, and broken teeth.

If the external drive gear is damaged, the gear must be replaced.

Check the drive gear bushing for wear and scuffing.

Measure the inside diameter of the external drive gear.

External Drive Gear Inside Diameter (No Bushing)

If the external drive gear is not within specifications, the gear must be replaced.

Inspect the lubricating oil pump internal gears for excessive wear, cracks, or broken teeth.

Erosion and pitting on the tip and root of the gear tooth is not acceptable. The gear must be replaced.

Measure the inside diameter of the internal idler gear.

Internal Idler Gear Inside Diameter

If the internal idler gear is not within specifications, it must be replaced.

Inspect the internal idler shaft for damage. Measure the outside diameter of the idler shaft.

Internal Idler Shaft Outside Diameter

If the idler shaft is not within specifications, it must be replaced.

Inspect the internal drive gear and shaft assembly for damage. Measure the outside diameter of the internal drive gear shaft.

Internal Drive Gear Shaft Outside Diameter

If the drive shaft is not within specifications, it must be replaced.

Lubricate the drive shaft with clean 15W-40 lubricating oil.

Install the internal idler gear onto the shaft.

Insert the internal drive gear and shaft assembly into the lubricating oil pump cover.

Press the external drive gear onto the shaft.

Install the ball first, then the spring.

Install the high pressure relief ball and spring into its bore in the lube pump housing.

No gasket is used when installing the lube pump cover.

Install the cover to the lube pump.

Tighten the center capscrews first, then the outside capscrews.

Install the six capscrews and tighten.

Install the external idler gear.

Insert the external idler gear retainer such that the holes are at the 3 and 9 o’clock position.

The idler gear retaining capscrew has left-hand threads.

Lubricate the oil pressure regulator valve and bore with clean engine oil.

Install the spring, valve, and cap with a new o-ring.

Use a new split pin to secure the cap to the lubricating oil pump body.

Turn the main drive gear by hand to check the gears for freedom of rotation.

Measure the end clearance of the external drive gear.

Drive Shaft End Clearance

Measure the gear backlash by mounting a dial indicator. Position the dial indicator contact point onto the lubricating oil pump external idler gear teeth.

With the external drive gear locked into place and the dial indicator contact in place, rotate the external idler gear clockwise and counterclockwise to measure the backlash.

Use the backlash measurement to classify and mark the pump per the following table.

Align dowels on oil pump with mounting holes in the cylinder block.

Install the oil pump, shims (if they were removed), and the four capscrews.

Tighten the capscrews.

Use a dial indicator, check the oil pump idler gear back lash.

Oil Pump Idler Gear Backlash

CAUTION  Improper gear lash can cause damage to the gear train and the lubricating oil pump.

Shims will be available in six different thicknesses in order to provide correct lash. The various thicknesses are identified by the color of the shim. Identify the number stamped on the pump (1) and the letter on the block (2). Use the following table to determine which shim should be used according to the stamped number and letter.

If the lubricating oil pump is not within specifications, the shims must be changed to proper thickness to give proper backlash.

• Install the lubricating oil suction tube. Refer to Procedure 007-035 in Section 7.
• Install the lubricating oil pan. Refer to Procedure 007-025 in Section 7.
• Fill the engine with lubricating oil. Refer to Procedure 007-037 in Section 7.
• Operate the engine and check for leaks.