3054 and 3056 Industrial and Generator Set Engines Caterpillar

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Hot engine components can cause injury from burns. Before performing maintenance on the engine, allow the engine and the components to cool.

Before you begin inspection of the turbocharger, be sure that the inlet air restriction is within the specifications for your engine. Be sure that the exhaust system restriction is within the specifications for your engine. Refer to Systems Operation/Testing and Adjusting, "Air Inlet and Exhaust System - Inspect".

The condition of the turbocharger will have definite effects on engine performance. Use the following inspections and procedures to determine the condition of the turbocharger.

• Inspection of the Compressor and the Compressor Housing

• Inspection of the Turbine Wheel and the Turbine Housing

• Inspection of the Wastegate

Inspection of the Compressor and the Compressor Housing

Remove the air cleaner from the compressor inlet.

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Illustration 1	g00766001
Typical example of a turbocharger (1) Turbine housing (2) Turbine wheel (3) Turbocharger

1. Inspect the compressor wheel for damage from a foreign object. If there is damage, determine the source of the foreign object. As required, clean the inlet system and repair the intake system. Replace the turbocharger. If there is no damage, go to Step 3.

2. Clean the compressor wheel and clean the compressor housing if you find buildup of foreign material. If there is no buildup of foreign material, go to Step 3.

3. Turn the rotating assembly by hand. While you turn the assembly, push the assembly sideways. The assembly should turn freely. The compressor wheel should not rub the compressor housing. The turbocharger must be replaced if the compressor wheel rubs the compressor wheel housing. If there is no rubbing or scraping, go to Step 4.

4. Inspect the compressor and the compressor wheel housing for oil leakage. An oil leak from the compressor may deposit oil in the aftercooler. Drain and clean the aftercooler if you find oil in the aftercooler.

   1. Check the oil level in the crankcase. If the oil level is too high, adjust the oil level.

   2. Inspect the air cleaner element for restriction. If restriction is found, correct the problem.

   3. Inspect the engine crankcase breather. Clean the engine crankcase breather or replace the engine crankcase breather if the engine crankcase breather is plugged.

   4. Remove the turbocharger oil drain line. Inspect the drain opening. Inspect the oil drain line. Inspect the area between the bearings of the rotating assembly shaft. Look for oil sludge. Inspect the oil drain hole for oil sludge. Inspect the oil drain line for oil sludge in the drain line. If necessary, clean the rotating assembly shaft. If necessary, clean the oil drain hole. If necessary, clean the oil drain line.

   5. If Steps 4.a through 4.d did not reveal the source of the oil leakage, the turbocharger has internal damage. Replace the turbocharger.

Inspection of the Turbine Wheel and the Turbine Housing

Remove the air piping from the turbine housing.

1. Inspect the turbine for damage by a foreign object. If there is damage, determine the source of the foreign object. Replace turbocharger (3). If there is no damage, go to Step 2.

2. Inspect turbine wheel (2) for buildup of carbon and other foreign material. Inspect turbine housing (1) for buildup of carbon and foreign material. Clean turbine wheel (2) and clean turbine housing (1) if you find buildup of carbon or foreign material. If there is no buildup of carbon or foreign material, go to Step 3.

3. Turn the rotating assembly by hand. While you turn the assembly, push the assembly sideways. The assembly should turn freely. Turbine wheel (2) should not rub turbine wheel housing (1). Replace turbocharger (3) if turbine wheel (2) rubs turbine housing (1). If there is no rubbing or scraping, go to Step 4.

4. Inspect the turbine and turbine housing (1) for oil leakage. Inspect the turbine and turbine housing (1) for oil coking. Some oil coking may be cleaned. Heavy oil coking may require replacement of the turbocharger. If the oil is coming from the turbocharger center housing go to Step 4.a. Otherwise go to “Inspection of the Wastegate”.

   1. Remove the turbocharger oil drain line. Inspect the drain opening. Inspect the area between the bearings of the rotating assembly shaft. Look for oil sludge. Inspect the oil drain hole for oil sludge. Inspect the oil drain line for oil sludge. If necessary, clean the rotating assembly shaft. If necessary, clean the drain opening. If necessary, clean the drain line.

   2. If crankcase pressure is high, or if the oil drain is restricted, pressure in the center housing may be greater than the pressure of turbine housing (1). Oil flow may be forced in the wrong direction and the oil may not drain. Check the crankcase pressure and correct any problems.

   3. If the oil drain line is damaged, replace the oil drain line.

   4. Check the routing of the oil drain line. Eliminate any sharp restrictive bends. Make sure that the oil drain line is not too close to the engine exhaust manifold.

   5. If Steps 4.a through 4.d did not reveal the source of the oil leakage, turbocharger (3) has internal damage. Replace turbocharger (3).

Inspection of the Wastegate

The wastegate controls the amount of exhaust gas that is allowed to bypass the turbine side of the turbocharger. This valve then controls the rpm of the turbocharger.

When the engine operates in conditions of low boost (lug), a spring presses against a diaphragm in the canister. The actuating rod will move and the wastegate will close. Then, the turbocharger can operate at maximum performance.

When the boost pressure increases against the diaphragm in the canister, the wastegate will open. The rpm of the turbocharger becomes limited. The rpm limitation occurs because a portion of the exhaust gases bypass the turbine wheel of the turbocharger.

The following levels of boost pressure indicate a problem with the wastegate:

• Too high at full load conditions

• Too low at all lug conditions

Note: The 3054B naturally aspirated engine is not equipped with a turbocharger.

The boost pressure controls the maximum rpm of the turbocharger, because the boost pressure controls the position of the wastegate. The following factors also affect the maximum rpm of the turbocharger:

• The engine rating

• The horsepower demand on the engine

• The high idle rpm

• Inlet air restriction

• Exhaust system restriction

Check the Wastegate for Proper Operation

1. Remove the heat shield from the turbocharger. Remove the guard for the wastegate.

2. Remove the boost line from the wastegate. Connect an air supply to the wastegate that can be adjusted accurately.

3. Fasten a dial indicator to the turbocharger so that the end of the actuator rod is in contact with the dial indicator. This will measure axial movement of the actuator rod.

4. Slowly apply air pressure to the wastegate so that the actuator rod moves 1.0 mm (0.039 inch). The air pressure should be within 107 to 117 kPa (15.5 to 17.0 psi). Ensure that the dial indicator returns to zero when the air pressure is released. Repeat the test several times. This will ensure that an accurate reading is obtained.

Adjustment of the Wastegate

If the reading that was obtained in "Check the Wastegate for Proper Operation" is not within the specification, then the wastegate must be adjusted.

1. Remove the dial gauge from the end of the actuator rod.

2. While the air pressure is still applied, release the locknut on the actuator arm. Remove the cotter pin that holds the actuator rod to the shaft.
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   NOTICE
   Use only the threaded rod to make adjustments to the wastegate. Do not pull or push the actuator rod. This could change the calibration of the wastegate and cause too much boost. Engine damage may result.

3. The length of the actuator rod needs to be reduced if the reading for the air pressure is too low. The length of the actuator rod must be increased if the reading for the air pressure is too high. Use a half of a turn to adjust the length.

4. Replace the actuator rod and install the cotter pin. Tighten the locknut. Release the air pressure.

5. Repeat the procedure for checking the wastegate for proper operation. If the air pressure is not correct, repeat the procedure for adjustment of the wastegate.

6. Install the guard for the wastegate. Install the heat shield for the turbocharger.