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Home >> Acura >> 2003 >> 3.2CL Base >> Repair and Diagnosis >> Engine Mechanical >> Mechanical >> 3.2L V6 Engine >> Overhaul >> Cylinder Head >> Valve Guide Replacement

Valve Guide Replacement

  1. Inspect valve stem-to-guide clearance. See VALVE STEM-TO-GUIDE CLEARANCE INSPECTION .
  2. Use appropriate air-impact valve guide driver (A) modified to fit the diameter of the valve guides. See Fig 1. In most cases, the same procedure can be done using the driver and a conventional hammer.
  3. Select the proper replacement guides and chill them in the freezer section of a refrigerator for about an hour.
  4. Use a hot plate or oven to evenly heat the cylinder head to 300°F (150°C). See Fig 2. Monitor the temperature with a cooking thermometer. DO NOT get head hotter than 300°F (150°C); excessive heat may loosen the valve seats.
  5. Working from the camshaft side, use the driver and an air hammer to drive the guide about .1" (2 mm) towards the combustion chamber. See Fig 3. This will knock off some of the carbon and make removal easier. Hold the air hammer directly in line with the valve guide to prevent damaging the driver. Wear safety goggles or a face shield.
  6. Turn the head over and drive the guide out toward the camshaft side of the head.
    Fig 1: Identifying Air-Impact Valve Driver
    G00297689Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 2: Heating Cylinder Head
    G00297690Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 3: Driving Guide Towards Combustion Chamber
    G00297691Courtesy of AMERICAN HONDA MOTOR CO., INC.
  7. If a valve guide won't move, drill it out with a 5/16" (8 mm) bit, then try again. Drill guides only in extreme cases; you could damage the cylinder head if the guide breaks.
  8. Remove the new guide(s) from the freezer, one at a time, as you need them.
  9. Apply a thin coat of clean engine oil to the outside of the new valve guide. Install the guide from the camshaft side of the head. Drive the guide in to the specified installed height (A) of the guide (B). See Fig 4 and VALVE GUIDE INSTALLED HEIGHT  . If you have all 12 guides to do, you may have to reheat the head.
    Fig 4: Installing Guide To Specified Height
    G00297692Courtesy of AMERICAN HONDA MOTOR CO., INC.
    VALVE GUIDE INSTALLED HEIGHT

    Application Specification - In. (mm)
    Intake .835-.874 (21.20-22.20)
    Exhaust .812-.852 (20.63-21.63)
  10. Coat both the reamer and the valve guide with cutting oil.
  11. Rotate the reamer clockwise the full length of the valve guide bore. See Fig 5.
  12. Continue to rotate the reamer clockwise while removing it from the bore.
  13. Thoroughly wash the guide with detergent and water to remove any cutting residue.
  14. Check the clearance with a valve. See VALVE STEM-TO-GUIDE CLEARANCE INSPECTION . Verify that the valve slides in the intake and exhaust valve guides without exerting pressure.
Fig 5: Rotating Reamer In Valve Guide
G00297693Courtesy of AMERICAN HONDA MOTOR CO., INC.
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