FixVault

Valve Clearance: Notes

  1. Bring camshaft into correct position for checking valves. Using a go-no-go gauge, check that clearance between valve tappet and heel of cam is to preliminary check specifications.
  2. If clearance is correct, no adjustment is necessary. If not, measure clearance of each valve using Special Tool (8391450) and a dial indicator. With measuring point of dial indicator resting on tip of cam, zero dial indicator.
  3. Lift valve depressor and note movement of dial indicator, indicating present valve clearance. Any valve not within adjust limit specifications should be adjusted.
  4. To adjust valves, remove camshaft, valve depressor and adjusting pads of valves needing adjustment. Measure thickness of adjusting pad with Special Tool (8391633) and calculate thickness of new pad required to bring valve clearance within adjustment specifications.
  5. Measured valve clearance plus adjusting pad thickness equals total distance between valve and cam. Total distance less the specified valve clearance, determines thickness of new adjusting pad to be installed.
  6. Install new adjusting pad, valve depressor, and camshaft and recheck that clearances are correct.
VALVE CLEARANCE SPECIFICATIONS (1)

Application Clearance In. (mm)
Preliminary Check
  Intake .006-.012 (.15-.30)
  Exhaust
    99, 99E & 900 .014-.020 (.35-.50)
    Turbo .016-.020 (.40-.50)
Adjustment Limit
  Intake .008-.010 (.20-.25)
  Exhaust
    99, 99E & 900 .016-.018 (.40-.45)
    Turbo .018-.020 (.45-.50)
(1) When checked 30 minutes after driving vehicle and at normal operating temperature.