Check as follows:
- Perform a crankcase pressure test and record the test results using the following: Crankcase pressure — Full load, maximum in. H2 O operating limits @ Rated speed = 5.0 in. H2 O. For test procedures, refer to “5.2.1 Crankcase Pressure Test” .
- Disconnect the air outlet line (2) from the air compressor, refer to “10.1 Air Compressor” in the “Special Equipment” chapter of the EPA07 DD15 Workshop Manual (DDC-SVC-MAN-0002).
Figure 1. Air Compressor Air Outlet Line
- Repeat step 1 and record the test results.
- Compare the results of test one with test two.
- If the engine crankcase pressure remained the same, check the turbocharger; refer to “4.3 Defective Turbocharger” .
- If the engine crankcase pressure decreased, replace the air compressor; .
- Remove the air compressor from the engine; refer to appropriate service manual, special equipment chapter.
- Replace the air compressor; refer to OEM guidelines.
- Install the air compressor to the engine; refer to “10.1 Air Compressor” in the “Special Equipment” chapter of the EPA07 DD15 Workshop Manual (DDC-SVC-MAN-0002).
- Start and run the engine.
- Perform a crankcase pressure test. Refer to the DD15 Service Manual (DDC-SVC-MAN-0002), preventive maintenance chapter.
- If the engine crankcase pressure exceeds 1.25 kPa (5 in. H2 O), refer to “5.3 Defective Turbocharger” . Shut down the engine.
- If the engine crankcase pressure is less than 1.25 kPa (5 in. H2 O), shut down the engine; no further troubleshooting is required.
Crankcase Pressure Test
Check the engine crankcase pressure as follows:
| To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. |
| ENGINE EXHAUST |
| To avoid injury from inhaling engine exhaust, always operate the engine in a well-ventilated area. Engine exhaust is toxic. |
- Start the engine.
- Run the engine and bring the engine coolant temperature to normal operating range, 88-96°C(190-205°F).
- Install J-48540–1 from the J-48540 kit on to the oil fill opening. Attach the gauge from kit J-48540, calibrated to read pressure in inches of H2 O, on to the adaptor.
- Run the vehicle to full load and rated speed. Use either chassis dynamometer or a trailer have the truck at full load.
- Measure and record crankcase pressure.
- Shut down the engine.
- Remove the adaptor from the port.
