Valve Adjustment

This procedure adjusts valve lash clearances on the 3.0L V6 Twin Turbo engine to ensure proper valve train operation and optimize engine performance.

Warnings

Tools required

Parts

• Valve cover gasket set (both banks) × 2 — Use OEM specification
• Valve cover bolt grommets × 1 — Use OEM specification
• Spark plug tube seals × 6 — Use OEM specification
• Engine oil × 1 — Selenia Racing 10W-60

Fluids

• Selenia Racing 10W-60 — 5.5 qt

Preparation

1. Ensure engine is completely cold (not run for at least 4 hours, ideally overnight).
2. Disconnect negative battery terminal and wait 10 minutes for system discharge.
3. Remove engine cover by releasing retaining clips.
4. Label and disconnect ignition coil connectors on both cylinder banks.
5. Remove ignition coils from all six cylinders.
6. Remove spark plugs and store in order.
7. Disconnect any wiring harness clips attached to valve covers.
8. Disconnect PCV hoses and breather hoses from both valve covers.
9. Position drain pan to catch any residual oil from valve covers.

Procedure

1. 1

   Remove left bank (driver side) valve cover
   Remove valve cover bolts in reverse sequence (outside to inside pattern). Carefully lift valve cover away from cylinder head. If stuck, tap gently with rubber mallet. Do not pry on gasket mating surfaces.
   Torque spec

   Cover Bolts18 Nm (13 lb-ft)
2. 2

   Remove right bank (passenger side) valve cover
   Remove valve cover bolts in reverse sequence. Lift valve cover away from cylinder head. Inspect valve train components for wear or damage before proceeding.
   Torque spec

   Cover Bolts18 Nm (13 lb-ft)
3. 3

   Rotate engine to TDC cylinder 1
   Using a 21mm socket on the crankshaft pulley bolt, rotate engine clockwise until cylinder 1 (front left) is at top dead center on compression stroke. Both intake and exhaust valves for cylinder 1 should be closed (rocker arms should have clearance). Verify timing marks align if visible.
4. 4

   Check valve lash on cylinder 1
   With cylinder 1 at TDC compression, check valve lash on both intake and exhaust valves. Insert feeler gauge between rocker arm and valve stem tip. Intake valve specification: 0.20-0.30mm cold. Exhaust valve specification: 0.35-0.45mm cold. Record measurements for each valve.
   ℹ️Proper lash should allow feeler gauge to slide with slight drag. Too loose or too tight requires adjustment.
5. 5

   Adjust valve lash if necessary on cylinder 1
   If adjustment needed, loosen the valve lash adjusting screw lock nut using a thin wrench. Hold the adjusting screw with a screwdriver while loosening. Turn adjusting screw clockwise to decrease clearance or counterclockwise to increase clearance. Once proper clearance is achieved using feeler gauge, hold adjusting screw firmly and tighten lock nut to specification. Recheck clearance after tightening as it may change slightly.
   ⚠Always hold the adjusting screw while tightening the lock nut to prevent the adjustment from changing.
   Torque spec

   Valve Lash Adjusting Screw Lock Nut20 Nm (15 lb-ft)
6. 6

   Rotate engine and check cylinder 5
   Rotate crankshaft 120 degrees clockwise (1/3 rotation). This positions cylinder 5 (rear left) at TDC compression. Check and adjust valve lash on cylinder 5 intake and exhaust valves using same procedure as cylinder 1.
   Torque spec

   Valve Lash Adjusting Screw Lock Nut20 Nm (15 lb-ft)
7. 7

   Rotate engine and check cylinder 3
   Rotate crankshaft another 120 degrees clockwise. This positions cylinder 3 (middle left) at TDC compression. Check and adjust valve lash on cylinder 3 intake and exhaust valves.
   Torque spec

   Valve Lash Adjusting Screw Lock Nut20 Nm (15 lb-ft)
8. 8

   Rotate engine and check cylinder 6
   Rotate crankshaft another 120 degrees clockwise. This positions cylinder 6 (rear right) at TDC compression. Check and adjust valve lash on cylinder 6 intake and exhaust valves.
   Torque spec

   Valve Lash Adjusting Screw Lock Nut20 Nm (15 lb-ft)
9. 9

   Rotate engine and check cylinder 2
   Rotate crankshaft another 120 degrees clockwise. This positions cylinder 2 (front right) at TDC compression. Check and adjust valve lash on cylinder 2 intake and exhaust valves.
   Torque spec

   Valve Lash Adjusting Screw Lock Nut20 Nm (15 lb-ft)
10. 10

    Rotate engine and check cylinder 4
    Rotate crankshaft another 120 degrees clockwise. This positions cylinder 4 (middle right) at TDC compression. Check and adjust valve lash on cylinder 4 intake and exhaust valves. All twelve valves have now been checked and adjusted.
    Torque spec

    Valve Lash Adjusting Screw Lock Nut20 Nm (15 lb-ft)
11. 11

    Clean gasket surfaces
    Thoroughly clean valve cover and cylinder head gasket mating surfaces using plastic scraper. Remove all old gasket material and oil residue. Clean surfaces with brake cleaner and lint-free cloth. Ensure surfaces are completely clean and dry before installing new gaskets.
    ⚠Do not use metal scrapers that could damage aluminum surfaces. Any scratches or gouges can cause oil leaks.
12. 12

    Install new valve cover gaskets and reinstall covers
    Install new valve cover gaskets and spark plug tube seals. Position valve covers carefully onto cylinder heads. Install valve cover bolts with new grommets. Tighten bolts in sequence from center outward to specified torque. Follow proper tightening pattern to ensure even gasket compression.
    ⚠Overtightening valve cover bolts can distort covers and cause leaks. Use torque wrench and follow sequence.
    Torque spec

    Cover Bolts18 Nm (13 lb-ft)
13. 13

    Reinstall spark plugs and ignition coils
    Install spark plugs in correct cylinders. Reconnect ignition coils and secure electrical connectors. Reattach all wiring harness clips, PCV hoses, and breather hoses to valve covers.
14. 14

    Final checks and start engine
    Reconnect negative battery terminal. Reinstall engine cover. Start engine and allow to idle. Listen for abnormal valve train noise. Check for oil leaks around valve covers. Allow engine to reach operating temperature and verify smooth operation.
    ℹ️Some light ticking for first few seconds after start is normal as oil pressure builds in valve train.

Reassembly

1. Ensure all electrical connectors are fully seated and locked.
2. Verify all hoses are properly reconnected and secured with clips.
3. Double-check valve cover bolts are torqued to specification in proper sequence.
4. Check engine oil level and top off if necessary with Selenia Racing 10W-60.

Verification

• Start engine and listen for proper valve train operation with no excessive noise or ticking.
• Check for oil leaks around both valve covers after engine reaches operating temperature.
• Take vehicle for short test drive and verify smooth engine operation at various RPM ranges.
• Recheck valve cover area for leaks after test drive.
• Monitor engine for first 100 miles to ensure valve adjustment remains stable.

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