To determine if a defective air compressor is causing excessive crankcase pressure, perform the following:
1.Perform a crankcase pressure test, refer to appropriate service manual, preventive maintenance chapter and record the test results. For crankcase pressure guidelines refer to Service Information Letter 02 TS-20 found on the DDC extranet.
2. Disconnect the air outlet line from the air compressor; see Figure 7-1; refer to appropriate service manual, special equipment chapter.
3. Repeat step 1 and record the test results.
4. Compare the results of test one with test two.
[a] If the engine crankcase pressure remained the same, check the turbocharger;
refer to section 7.3.
[b] If the engine crankcase pressure decreased, repair the air compressor; refer to section 7.2.1.
7.2.1
Air Compressor Repair
Perform the following steps to repair the defective air compressor:
1. Remove the air compressor from the engine; refer to appropriate service manual, special equipment chapter.
2. Install the repaired air compressor to the engine; refer to appropriate service manual, special equipment chapter.
3. Verify repair of the air compressor; refer to section 7.2.1.1.
7.2.1.1
Test Engine with Repaired Air Compressor
Perform the following steps to determine if a repaired air compressor resolved the excessive crankcase pressure:
1. Start and run the engine.
2. Perform a crankcase pressure test. Refer to appropriate service manual, preventive maintenance chapter. For crankcase pressure guidelines refer to Service Information Letter 02 TS-20 found on the DDC extranet.
[a] If the engine crankcase pressure is within 1.25 kPa (5 in. H O), no further troubleshooting is required. Shut down the engine.
[b] If the engine crankcase pressure is not within 1.25 kPa (5 in. H2O), check the turbocharger, refer to section 7.3. Shut down the engine.
