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Home >> Ford >> 2003 >> Excursion 7.3 F, RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System & Component Testing - 7.3L Diesel >> Engine Performance Diagnostic Procedures >> Test 11: Crankcase Pressure Test >> Recommended Procedure
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Recommended Procedure

  1. Ensure engine is at normal operating temperature. A cold engine will give higher readings. Remove turbocharger inlet pipe ducting. Remove inlet pipe and elbow that connects to air filter housing. Using cap provided in Engine Pressure Tester (014-00761), block air filter housing outlet. See Fig 1. Install a protective screen over turbocharger inlet.
  2. Screw Crankcase Orifice Restrictor Tool (014-00743) and Crankcase Pressure Test Adapter (014-00743) into oil fill cap hole. See Fig 1. Connect adapter to Magnehelic® pressure gauge at engine pressure tester. Ensure gauge has been zeroed.
  3. Start engine. Monitor pressure gauge and raise engine speed to 3400 RPM for about 30 seconds. DO NOT block hole at top of crankcase orifice restrictor. If pressure is less than 3 in. H2O, go to TEST 12: CYLINDER CONTRIBUTION TEST . If pressure is 3 in. H2O or more, check engine mechanical condition (compression rings, cylinder bores, valves, etc.). Repair as necessary.
Fig 1: Checking Crankcase Pressure
G00053813Courtesy of FORD MOTOR CO.