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Valve Guide Servicing

  1. With cylinder head removed, remove valve and valve spring at valve guide where service is required. Place cylinder head with machined face down on clean surface. Drive valve guide down into combustion space with suitable drift.
  2. Drift should be hardened steel 0.438" (11.1 mm) in diameter and not less than 4" (101 mm) long. Drift should be machined to 0.281" (7.14 mm) for a distance of 1" (25.4 mm) at one end. This will allow drift to engage bore of guide.
  3. When installing new guides, they should be driven in from top of cylinder head. Intake valve guides must be inserted with largest chamfer at top. Exhaust valve guides should have counterbored ends at bottom. Drive guides into combustion spaces until they are 0.540" (13.7 mm) above machined surface of valve spring seating surface.
    Fig 1: Valve Guides
    G09349971Courtesy of NOT AVAILABLE
    VALVE SPRINGS

    Engine Free Length In. (mm) PRESSURE Lbs. @ In. (kg @ mm)
    Valve Closed Valve Open
    1275 cc      
      Inner 1.703 25@1.270 44@0.952
        (43.256) (11.3@32.26) (20@24.18)
      Outer 1.828 51@1.383 87@1.065
        (46.431) (23.1@35.13) (39.5@27.05)