C9.3 Marine Generator Set Engines Caterpillar

Visual Inspection

Inspect the following parts at each oil change:

• Air lines

• Hoses

• Gasket joints

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Pressurized air can cause personal injury. When pressurized air is used for cleaning, wear a protective face shield, protective clothing, and protective shoes.

Ensure that the constant torque hose clamps are tightened to the correct torque. Refer to Torque Specifications, SENR3130, "Standard Torque for Constant Torque Hose Clamps" for the correct torque. Check the welded joints for cracks. Ensure that the brackets are tightened in the correct positions. Ensure that the brackets are in good condition. Use compressed air to clean any debris or any dust from the aftercooler core assembly. Inspect the fins of the aftercooler for the following conditions:

• Damage

• Debris

• Corrosion

Use a stainless steel brush to remove any corrosion.

Note: When parts of the aftercooler system are repaired or replaced, a leak test is recommended.

Inlet Manifold Pressure

Normal inlet manifold pressure with high exhaust temperature can be caused by blockage of the aftercooler core. Clean the aftercooler core.

Low inlet manifold pressure and high exhaust manifold temperature can be caused by any of the following conditions:

Plugged air cleaner - Clean the air cleaner or replace the air cleaner, as required. Refer to the Operation and Maintenance Manual, "Engine Air Cleaner Element (Dual Element) - Clean/Replace".

Blockage in the air lines - Blockage in the air lines between the air cleaner and the turbocharger must be removed.

Inlet manifold leak - An inlet manifold leak can be caused by the following conditions: loose fittings and plugs, missing fittings and plugs, damaged fittings and plugs and leaking inlet manifold gasket.

Air System Restriction

Pressure measurements should be taken at the inlet manifold and at the turbocharger outlet.

Use the differential pressure gauge of the 1U-5470 Engine Pressure Group or use the 198-4240 Digital Pressure Indicator. Use the following procedure in order to measure the restriction of the aftercooler:

1. Connect the vacuum port of the differential pressure gauge to port (10).

2. Connect the pressure port of the differential pressure gauge to port (11).

3. Record the value.

The air lines and the cooler core must be inspected for internal restriction when both of the following conditions are met:

• Air flow is at a maximum level.

• Total air pressure drop of the charged system exceeds 16.9 kPa (5 in Hg).

If a restriction is discovered, proceed with the following tasks, as required:

• Clean

• Repair

• Replacement

Leak Test for the Sea Water Cooling System

Test for Water Leaks

1. Remove the aftercooler core from the engine. Refer to Disassembly and Assembly, "Aftercooler and Aftercooler Core".

2. Thoroughly clean the aftercooler core.

3. Plug the fittings of the aftercooler core.

4. Pressurize the aftercooler core to 240 kPa (35 psi).

5. Spray the aftercooler core with a mixture of water and a soap solution. Look for air bubbles that form on the aftercooler core.

Test for Air Leaks

The bottom opening of the aftercooler must be closed in order to perform the following pressure test. A cover may need to be fabricated in order to plug the opening.

1. Remove the aftercooler from the engine. Refer to Disassembly and Assembly, "Aftercooler and Aftercooler Core".

2. Assemble the aftercooler on the bench. Refer to Disassembly and Assembly, "Aftercooler and Aftercooler Core".

3. Plug the openings of the aftercooler and pressurize the aftercooler to 205 kPa (30 psi).

4. Spray the aftercooler core with a mixture of water and a soap solution. Look for air bubbles that form on the aftercooler core.

Turbocharger Failure

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Personal injury can result from air pressure. Personal injury can result without following proper procedure. When using pressure air, wear a protective face shield and protective clothing. Maximum air pressure at the nozzle must be less than 205 kPa (30 psi) for cleaning purposes.

If a turbocharger failure occurs, remove the aftercooler core. Internally flush the aftercooler core with a solvent that removes oil and other foreign substances. Wash the aftercooler with hot, soapy water. Thoroughly rinse the aftercooler with clean water and blow dry the aftercooler with compressed air. Blow dry the assembly in the reverse direction of normal air flow. To make sure that the whole system is clean, carefully inspect the system.

Dynamometer Test

In hot ambient temperatures, dynamometer tests for models with an aftercooler can add a greater heat load to the jacket water cooling system. Therefore, the jacket water cooling systems temperature must be monitored. The following measurements may also need a power correction factor:

• Inlet air temperature

• Fuel API rating

• Fuel temperature

• Barometric pressure

With dynamometer tests for engines, use the FT-1438 Aftercooler Gp (DYNAMOMETER TEST). This tool provides a water-cooled aftercooler in order to control the inlet air temperature to 43 °C (110 °F).