Hyundai Sonata: Cylinder Head Assembly / 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
Remove the cylinder head cover. (Refer to Cylinder Head Assembly - Cylinder Head Cover)
2
Set the No. 1 cylinder to TDC/compression.
1. Turn the crankshaft pulley and align its groove with the alignment mark on the timing chain cover.
2. Make sure the intake and exhaust CVVT sprocket timing marks are aligned in a straight line with the cylinder head surface, as shown in the illustration. If not, turn the crankshaft one full revolution (360°).
  
  Do not turn the crankshaft damper pulley counterclockwise.
3. Mark the timing chain links corresponding to the timing marks on the CVVT sprockets with indelible marker.
3
Remove the exhaust oil control valve (OCV) adapter (A).
4
Inspect the valve clearance.
1. Check only the intake valves of No. 1 and No. 2 cylinders and the exhaust valves of No. 1 and No. 3 cylinders for clearance.
  
  A. Using a feeler gauge, measure the clearance between the tappet and the camshaft base circle.
  
  B. Record valve clearance measurements that are out of specification. They will be used later to determine the required tappet for adjustment.
  
  Valve clearance specifications (engine coolant temperature: 20 °C [68°F]) Limit Intake: 0.17 ~ 0.23 mm (0.0067 ~ 0.0091 in) Exhaust: 0.22 ~ 0.28 mm (0.0087 ~ 0.0110 in)
2. Turn the crankshaft pulley one full revolution (360° clockwise) and align its groove with the alignment mark on the timing chain cover.
3. Check the intake valves of No. 3 and No. 4 cylinders and the exhaust valves of No. 2 and No. 4 cylinders for clearance.
5
Remove the engine mount support bracket.
1. Place a jack under the oil pan.
  
  Place a wooden block between the jack and the oil pan to avoid damaging the oil pan.
2. Disconnect the engine ground cable (A).
3. Remove the engine mount support bracket (A).
4. Raise the engine slightly with a jack to create space for removing the timing chain tensioner.
6
Adjust the intake and exhaust valve clearance.
1. Remove the bolt (A) from the service hole in the timing chain cover.
2. Lock the timing chain tensioner in the fully retracted position. Insert a pick tool into the service hole in the timing chain cover and lift the left side of the ratchet plate (A) on the tensioner so that the pawl (B) engages inside the tensioner behind the ratchet.
3. Remove the camshaft bearing caps (A) in the order shown below.
4. With the pawl lifted, have an assistant raise the exhaust CVVT and camshaft (A) to allow the tensioner plunger (B) to retract.
5. When the tensioner plunger is fully retracted, lift the left side of the ratchet plate (A) again through the service hole in the chain cover to align the ratchet plate hole with the hole in the tensioner housing behind the ratchet plate, then lock the tensioner by inserting a pick tool through the ratchet plate and the housing hole.
6. Separate the exhaust camshaft (A) from the exhaust CVVT by removing the bolt.
7. Remove the exhaust CVVT (A) from the timing chain.
8. Remove the intake CVVT and camshaft (A).
  
  Secure the timing chain to the engine mount with a cable tie or belt so the timing chain does not fall when removing the intake CVVT and camshaft.
9. Remove the tappet(s) with out-of-specification valve clearance from the cylinder head.
10. Using a micrometer, measure the thickness of the removed tappet.
11. Calculate the thickness of the new tappet so that the valve clearance is within specification. Valve clearance (engine coolant temperature: 20 °C) T: Thickness of removed tappet. A: Measured valve clearance. N: Thickness of new tappet. Intake: N = T + [A - 0.20 mm (0.0079 in)] Exhaust: N = T + [A - 0.25 mm (0.0098 in)]
12. Select a new tappet with a thickness as close as possible to the calculated value.
  
  Shims are available in 41 sizes in 0.015 mm (0.0006 in) increments from 3.00 mm (0.118 in) to 3.690 mm (0.1417 in).
13. Install the new tappet into the cylinder head.
14. Install the intake CVVT and camshaft (A) with the timing mark on the intake CVVT sprocket aligned with the mark (painted link) on the timing chain.
15. Install the exhaust CVVT sprocket (A) with the alignment mark facing outward. Align the exhaust CVVT sprocket mark with the mark (painted link) on the timing chain.
16. Install the exhaust camshaft (A) onto the exhaust CVVT.
  Tightening torque: 63.7 ~ 74 N·m
17. Remove the pick tool from the service hole in the timing chain cover.
18. Make sure that the alignment marks on the intake and exhaust CVVT sprockets are aligned, as shown in the illustration.
19. Install the bolt (A) into the service hole in the timing chain cover.
  Tightening torque: 27.5 ~ 30 N·m
20. Install the engine mount bracket.
  1. Install the engine mount bracket (A).
    Tightening torque: 88.3 ~ 108 N·m
  2. Connect the engine ground cable (A).
    Tightening torque: 10.8 ~ 13.7 N·m
  3. Remove the jack from the oil pan.
21. Install the camshaft bearing caps in the order shown below. Tightening torque: Step 1 M6 bolt: 5.9 N·m M8 bolt: 9.8 N·m Step 2 M6 bolts: 11.8 ~ 13.7 N·m M8 bolts: 18.6 ~ 23 N·m
22. Turn the crankshaft two revolutions clockwise in the normal direction of rotation, and make sure that the marks on the intake and exhaust CVVT sprockets are aligned in a straight line on the cylinder head surface.
23. Recheck the valve clearance. Valve clearance (engine coolant temperature: 20 °C) [Specification] Intake: 0.17 ~ 0.23 mm (0.0067 ~ 0.0091 in.) Exhaust: 0.22 ~ 0.28 mm (0.0087 ~ 0.0110 in.)
24. Install the exhaust oil control valve (OCV) adapter (A).
  Tightening torque: 9.8 ~ 11.8 N·m
25. Install the cylinder head cover. (Refer to Cylinder Head Assembly - "Cylinder Head Cover")