Hyundai Sonata LF Quiz
Engine Mechanical System

CVVT and Camshaft Repair Procedures

In this manual: Engine Mechanical System
General Information — 9Engine Mechanical System — 90Engine Electrical System — 58Emission Control System — 24Engine Control System/Fuel System — 114Drive Shaft and Axle — 15Suspension System — 35Steering — 19Restraints — 50Brake System — 54Body (Interior and Exterior) — 213Body Electrical System — 241Heating, Ventilation, and Air Conditioning — 56DCT (Dual Clutch Transmission) System — 52
27steps
~162min
4/5difficulty
010203040505.94N·mlb·ft
Tightening torque found on this page
Done 0 of 27

Removal

  1. Remove the cylinder head cover. (Refer to Cylinder Head Assembly - Cylinder Head Cover)
  2. Turn the crankshaft damper pulley so that the No. 1 piston is at top dead center (TDC).
    1. Turn the crankshaft damper pulley and align its groove with the mark on the timing chain cover (0° mark on the scale).
    2. Make sure that the TDC alignment marks on the intake and exhaust CVVT sprockets are aligned in a straight line on the cylinder head surface, as shown in the illustration. If not, turn the crankshaft damper pulley 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. Remove the camshaft bearing caps (A) in the order shown in the illustration.
  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. Remove the bolt (A) from the service hole in the timing chain cover.
  7. Lock the timing chain tensioner in the fully retracted position.
    1. Insert a pick tool into the service hole in the timing chain cover and lift the pawl (B) inside the tensioner, from the left side of the ratchet plate (A) of the tensioner.
    2. With the pawl raised, ask an assistant to lift the exhaust CVVT and camshaft (A) to allow the tensioner plunger (B) to retract.
    3. 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.
  8. Separate the exhaust camshaft (A) from the exhaust CVVT by removing the bolt.
  9. Remove the exhaust CVVT (A) from the timing chain.
  10. 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.
  11. Remove the intake CVVT (A) from the intake camshaft (B).
    When removing the CVVT bolt, hold the hex portion (B) of the camshaft with a wrench to prevent the camshaft from rotating.

Inspection

Camshaft
  1. Measure the cam lobe height with a micrometer and check the cam lobe surface for wear. If necessary, replace the camshaft.

    Cam lobe height Intake: 44.15 mm (1.738 in) Exhaust: 43.55 mm (1.715 in)

  2. Inspect the camshaft journal surface for wear. If the camshaft journal is severely damaged, replace the camshaft.
  3. Inspect the camshaft journal oil clearance.
    1. Clean the camshaft journals and bearing caps.
    2. Place the camshafts on the cylinder head.
    3. Place a strip of Plastigage on each camshaft journal.
    4. Install the bearing caps and tighten the bolts to the specified torque. 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
      Do not rotate the camshaft.
    5. Remove the bearing caps.
    6. Measure the Plastigage at its widest point. If the clearance is greater than specified, replace the camshaft. If necessary, replace the bearing caps and cylinder head as a set. Camshaft bearing cap oil clearance Standard: 0.027 ~ 0.058 mm (0.0011 ~ 0.0023 in.) Limit: 0.1 mm (0.0039 in.)
  4. Inspect the camshaft end play.
    1. Inspect the camshaft end play.
    2. Measure the camshaft end play by moving the camshaft back and forth using a dial indicator. If the end play is greater than specified, replace the camshaft. If necessary, replace the bearing caps and cylinder head as a set. Camshaft end play Standard: 0.1 ~ 0.2 mm (0.0039 ~ 0.0079 in.)
    3. Remove the camshafts.
  5. Inspect the CVVT for smooth rotation.
    1. Clamp the camshaft in a vise. Be careful not to damage the cam lobes and journals in the vise.
    2. Make sure the CVVT is locked by turning it clockwise or counterclockwise. It should not rotate.
    3. Intake CVVT: Tape over one of the two advance holes in the camshaft journal. Exhaust CVVT: Tape over one of the two retard holes in the camshaft journal.
    4. Intake CVVT: Apply approx. 150 kPa (1.5 kgf/cm², 21 psi) of compressed air to the unsealed supply hole to unlock the lock. Exhaust CVVT: Apply approx. 150 kPa (1.5 kgf/cm², 21 psi) of compressed air to the unsealed retard hole to unlock the lock.
      When applying compressed air, cover the oil passages with a cloth to prevent oil from splashing.
    5. Intake CVVT: While applying compressed air, rotate the CVVT in the advance direction (counterclockwise) within its phase range, and check that the CVVT rotates smoothly. Exhaust CVVT: While applying compressed air, rotate the CVVT in the retard direction (clockwise), and check that the CVVT rotates smoothly. CVVT Phase Range Intake: 25°±1° (from most retarded position to most advanced position) Exhaust: 20°±1° (from most advanced position to most retarded position)
    6. Intake CVVT: Rotate the CVVT to the most retarded position (clockwise), then make sure the CVVT is locked. Exhaust CVVT: Rotate the CVVT to the most advanced position (counterclockwise), then make sure the CVVT is locked.
CVVT (Continuously Variable Valve Timing) Assembly

Installation

  1. Install the intake CVVT (A) onto the intake camshaft.

    Tightening torque: 63.7 ~ 74 N·m
    When installing the CVVT bolt, hold the hexagonal portion (B) of the camshaft with a wrench to prevent the camshaft from rotating.
  2. 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.
  3. 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.
  4. Install the exhaust camshaft (A) onto the exhaust CVVT.

    Tightening torque: 63.7 ~ 74 N·m

  5. Remove the pick tool from the service hole in the timing chain cover.
  6. Make sure that the alignment marks on the intake and exhaust CVVT sprockets are aligned, as shown in the illustration.
  7. Install the bolt (A) into the service hole in the timing chain cover.

    Tightening torque: 27.5 ~ 30 N·m

  8. 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.
  9. Install the camshaft bearing caps (A) in the order shown in the illustration, and tighten the bolts to the specified torque. 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
  10. Install the exhaust oil control valve (OCV) adapter (A).

    Tightening torque: 9.8 ~ 11.8 N·m
    When installing the OCV adapter, make sure that the O-ring of the front camshaft bearing cap is correctly seated.
  11. Install the cylinder head cover. (Refer to Cylinder Head Assembly - "Cylinder Head Cover")

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