Valve Clearance Adjustment

Valve Clearance Inspection and Adjustment

Inspect and adjust the valve clearance with the engine cold (engine coolant temperature: 20 °C) and the cylinder head installed on the cylinder block.

1. 1
   Remove the cylinder head cover. (Refer to Timing System in this group)
2. 2
   Set the No. 1 cylinder to TDC/compression.

   1. Turn the crankshaft pulley and align its groove with the "T" alignment mark on the lower timing chain cover.

      

   2. Make sure the TDC marks (A) on the CVVT sprockets are in a straight line with the cylinder head surface, as shown in the illustration. Otherwise, turn the crankshaft one full revolution (360°).

      

3. 3
   Inspect the valve clearance.

   1. Check only the valve indicated in the illustration. Measure the valve clearance.

      

      • Using a feeler gauge, measure the clearance between the tappet and the camshaft base circle.
      • Record the valve clearance measurements that are out of specification. They will be used later to determine the required tappet replacement.
      Valve clearance (engine coolant temperature: 20 °C [68°F]) [Specification] Intake: 0.17 ~ 0.23 mm (0.0067 ~ 0.0090 in) Exhaust: 0.27 ~ 0.33 mm (0.0106 ~ 0.0129 in)
   2. Turn the crankshaft pulley one full revolution (360°) and align the groove with the "T" alignment mark on the timing chain cover.
   3. Check only the valves indicated in the illustration. Measure the valve clearance.

      

4. 4
   Adjust the intake and exhaust valve clearance.

   1. Set the No. 1 cylinder to TDC/compression.
   2. Mark the timing chains (A) to the alignment marks on the CVVT sprockets.

      

   3. Turn the crankshaft pulley 15° clockwise.
   4. Loosen the timing chain tension using SST 09240-2G000.

      A.	Remove the bolt (A) from the service hole in the timing chain cover. It may be necessary to insert an M8 x 1.25 tap into the hole to clean the sealant from the threads. Make sure no debris enters the engine through the open bolt hole.

      B.

      Pull and turn the loop (A) on SST 09240-2G000 to allow the spring-loaded shaft (B) to be pulled back and locked against the spring. Apply a small amount of light grease to the tool threads, then screw it into the hole in the timing cover until you feel it contact the tensioner. Then back the tool out approximately one turn.

      C.	Turn the loop to unlock the tool.

      D.

      Slowly turn the tool counterclockwise. Depending on the position of the pin on the tool, several clicks may be heard as the pin moves over the pawl and shaft. As you turn, you should feel the spring-loaded pawl rise. After the pawl is raised, tighten the lock nut (A) and lift the timing chain and cam sprocket onto the camshaft.

   5. Remove the front camshaft bearing cap.
   6. Remove the exhaust camshaft bearing cap and the exhaust camshaft.
   7. Remove the intake camshaft bearing cap and the intake camshaft.

      When disconnecting the timing chain from the CVVT sprocket, tie or hold the timing chain so that it does not drop into the timing chain cover.

   8. Tie the timing chain to prevent it from moving.

      Be careful not to drop anything into the timing chain cover.

   9. Measure the thickness of the removed tappet using a micrometer.

      

   10. Calculate the thickness of the new tappet so that the valve clearance is within the specified value. Valve clearance [Engine Coolant Temperature: 20 °C] T: Thickness of the removed tappet. A: Measured valve clearance. N: Thickness of the new tappet. Intake: N = T + [A - 0.20 mm (0.0079 in.)] Exhaust: N = T + [A - 0.30 mm (0.0118 in.)]
   11. Select a new tappet with a thickness as close as possible to the calculated value.

       Shims are available in 47 sizes in 0.015 mm (0.0006 in.) increments from 3.00 mm (0.118 in.) to 3.690 mm (0.1452 in.).

   12. Install the new tappet onto the valve stem/spring.
   13. While holding the timing chain, install the intake camshaft and CVVT assembly.
   14. Align the timing marks (A) on the timing chains and CVVT sprockets.

       

   15. Install the exhaust camshaft and CVVT assembly.
   16. Install the front bearing cap.
   17. Install the service hole bolt after removing the SST from the service hole.

       Tightening torque: 11.8 ~ 14.7 N·m

       To remove the ratchet holder, loosen the lock nut and pull out the center rod.

   18. Turn the crankshaft two revolutions in the normal operating direction (clockwise), then check that the TDC marks (A) on the CVVT sprockets are in a straight line on the cylinder head surface.

       

   19. Recheck the valve clearance. Valve clearance [Engine Coolant Temperature: 20 °C] [Specification] Intake: 0.17 - 0.23 mm (0.0067 - 0.0090 in.) Exhaust: 0.27 - 0.33 mm (0.0106 - 0.0129 in.)