FixVault
Home › Jaguar › 1992 › XJS 2D Convertible › Repair and Diagnosis › Engine Performance › Engine Controls - Adjustments › Engine Mechanical › Adjusting Valve Clearance

Adjusting Valve Clearance

  1. If valve clearance needs adjustment, remove rubber grommet from front of timing cover. Grommet is located on right side of timing cover just above water pump.
  2. Insert chain tensioner releaser/retainer through timing cover access hole. With a twisting motion, release locking catch on timing chain tensioner. See Fig 1 . Install chain tensioner releaser/retainer.
    Fig 1: Retracting Timing Chain Tensioner (XJS)
    G90D15571Courtesy of JAGUAR CARS, INC.
  3. The hook on chain tensioner releaser/retainer arm fits into a slot on tensioner. Pull up on chain tensioner releaser/retainer and retract timing chain tensioner until locking catch is engaged. See Fig 1 .
  4. Rotate engine until timing gauge can be inserted into recess of left camshaft. See Fig 2 . Note 2 uppermost camshaft sprocket retaining bolts. Remove timing gauge and rotate engine until the 2 lower camshaft sprocket retaining bolts become accessible.
  5. Using a punch and hammer, open lock tabs and remove the 2 lower sprocket retaining bolts. Rotate engine to TDC position and refit timing gauge. Remove 2 remaining camshaft sprocket bolts and fit camshaft sprocket retainer to camshaft sprockets. See Fig 3 .
    Fig 2: Checking Camshaft Timing (XJS)
    G90E15572Courtesy of JAGUAR CARS, INC.
    Fig 3: Securing Camshaft Sprocket (XJS)
    G90F15573Courtesy of JAGUAR CARS, INC.
  6. Starting from center, remove camshaft bearing caps one at a time. Note bearing cap to camshaft tower relationship. Corresponding numbers are marked on bearing cap and cam tower. Remove left camshaft. Note original location and remove cam followers.
  7. Remove valve adjusting pads one at a time. Measure original pad thickness using a 1" micrometer and note reading. Using this measurement and measurement reading made in step 7) of CHECKING CLEARANCE  , calculate size of shim required. Select adjusting pads equal to measurement and install on top of valve spring collar.
  8. Adjusting pads are available from .085-.110" (2.16-2.79 mm) in increments of .001" (.03 mm). Pads are coded with letters "A" to "Z", each letter corresponding to a thickness increase of one size. Install camshaft followers into their original locations.
  9. Lubricate camshaft journals with clean engine oil. Install camshaft using timing gauge to position camshaft correctly. Install bearing caps and progressively tighten nuts to 96-120 INCH lbs. (11-13.5 N.m). Ensure timing gauge is in position.
  10. Engage camshaft sprocket to camshaft. Install one lock tab and bolt. Remove timing gauge and camshaft sprocket retainer. Rotate engine, and install remaining lock tab and cam sprocket retaining bolts. Tighten to 17-20 ft. lbs. (23-27 N.m). Recheck valve clearances and repeat adjustment procedure if necessary. Repeat steps 6)-10) for right side valve adjustment.
  11. Fit chain tension retainer and raise timing chain tensioner slightly. Insert release tool through timing cover access hole. Release locking catch and allow tensioner to expand. Remove chain tension retainer and release tool.
  12. Install new rubber grommet in front timing cover. Clean cam cover gasket surfaces. Install new cam cover seals and gaskets. Install cam covers. Tighten bolts to 96 INCH lbs. (11 N.m). To complete installation, reverse removal procedure. Evacuate and recharge A/C system.
About FixVault