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SERIES 50 DEFECTIVE CRANKSHAFT MAIN BEARING SHELLS

To determine if defective crankshaft main bearing shells are causing low oil pressure, perform the following: ‪

  1. Check main bearing to crankshaft journal clearances; refer to Section .
    1. If main bearing shell-to-journal clearance is within 0.040-0.151 mm (0.0016-0.006 in.), check oil pump assembly; refer to Section .
    2. If main bearing shell-to-journal clearance is not within 0.040-0.151 mm (0.0016-0.006 in.); refer to Section .

Crankshaft Main Bearing Shell Repair

Perform the following steps to repair crankshaft main bearing shells: ‪

  1. Remove and replace defective crankshaft main bearing shells; refer to Section .
  2. Verify crankshaft main bearing shells repair: refer to Section .
Test Engine with New Crankshaft Main Bearing Shells

Perform the following to determine if repaired relief valve resolved low oil pressure: ‪

  1. Install the Diagnostic Data Reader to the vehicles Display Data Line Adaptor, see Figure 24089 ; refer to OEM guidelines.
  2. Start and run engine between 1800 r/min.
  3. Visually examine the DDR for oil pressure reading.
    1. If the DDR indicates 241 kPa (35 lb/in.2 ), at 1800 r/min, shut down the engine and disconnect the DDR. No further troubleshooting is required.
    2. If the DDR indicates less than 241 kPa (35 lb/in.2 ), at 1800 r/min, shut down the engine and disconnect the DDR. Check the oil pump assembly; refer to Section .