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Follow these steps to verify Camshaft Position Sensor (CMP) clearance. ‪

  1. Remove CMP sensor mounting bolt from engine front cover and pull CMP sensor out. Clean sensor mounting surface; see Figure 31266 .

    Remove CMP Sensor

  2. Manually rotate the crankshaft at least two complete revolutions in a clockwise direction when viewing the engine from the front. This ensures the CMP sensor air gap is at its maximum with the camshaft gear in contact with its rear thrust face.

    Note: Ensure the following measurement is up to the tooth on the trigger wheel. Do not measure into the window between the teeth.

  3. Using a depth micrometer or a precision caliper, carefully measure the distance to the nearest one thousandth of an inch from the CMP sensor mounting surface to the camshaft gear trigger wheel tooth; see Figure 31297 . Record this measurement in the appropriate box on the worksheet.

    Measuring Camshaft Position Sensor Clearance

  4. Manually rotate crankshaft 180 degrees in a clockwise direction, when viewed from the front of the engine, and repeat step 3. Continue this process two more times so that the distance from the cover to the trigger wheel is measured at four locations. Variations in these measurements determine run out of the trigger wheel. Variation should not exceed 0.005 inches.
  5. Using a depth micrometer or precision caliper carefully measure CMP sensor from the tip to its mounting flange; see Figure 31299 . Record this dimension in the appropriate box on work sheet.

    Measuring Depth Micrometer

  6. Perform the math as directed on the work sheet then select appropriate combination of shims from shim kit, if required. Refer to the Series 40E Parts Manual for the proper kit part number.

    Note: Use the proper combination of shims to achieve a measurement as close to 0.30 in. as possible.

  7. Install the CMP sensors with the shims required. Ensure that the shims are centered on the CMP sensor flange. Use a small amount of grease to hold then if necessary. Reconnect sensor wiring harness and test engine. Complete the CMP sensor air gap analysis as listed in Table .




    1. ‪

    Rotate crankshaft clockwise at least two revolutions. ‪

    2. ‪

    Measure distance from CMP sensor mounting surface to trigger wheel tooth. ‪

    3. ‪

    Rotate crankshaft clockwise, 1/2 turn, repeat step 2. ‪

    4. ‪

    Rotate crankshaft clockwise, 1/2 turn, repeat step 2. ‪

    5. ‪

    Rotate crankshaft clockwise, 1/2 turn, repeat step 2. ‪

    6. ‪

    Add measurements from steps 2 thru 5.= ‪

    7. ‪

    Obtain average dimension by dividing by 4:= ‪

    8. ‪

    Measure CMP sensor length from tip to surface of mounting flange. ‪

    9. ‪

    Subtract step 8 from step 7. ‪

    10. ‪

    Desired air gap: ‪

    0.030 in. ‪

    11. ‪

    Subtract step 10 from step 9. (This is the required thickness.) ‪

    12. ‪

    Select shims as required from shim kit (two 0.005 in. and two 0.010 in. shims provided). Use one or more shims from kit to get as close as possible to thickness determined in step 12. Measure thickness of shim(s). Enter shim pack thickness here: ‪

    13. ‪

    Place shims over the CMP sensor tip. Insure shims are centered on CMP sensor flange. Install CMP sensor/shim assembly in front cover. Torque clamp bolt to 15 lb-ft. (20 Nm) and reconnect wiring harness. ‪

    Camshaft Position Sensor Clearance Worksheet