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Removal and Installation: Removal

WARNING: This page is about a different car, the 2004 Nissan Sentra. However, it is still accessible from the selected car via links, so may be relevant.
  1. Remove the rocker cover. Refer to "ROCKER COVER ".
  2. Remove the cylinder head front cover.
    • Move harness secured to the front surface beforehand.
  3. Set No. 1 cylinder at TDC of its compression stroke.
    Fig 1: Rotating Crankshaft Pulley Clockwise And Aligning Yellow Paint Mark With Timing Indicator
    G00773944Courtesy of NISSAN MOTOR CO., U.S.A.
    1. Remove the RH splash cover.
    2. Rotate crankshaft pulley clockwise and align the yellow paint mark with the timing indicator.
    3. Confirm mating marks stamped on intake and exhaust sprockets are located as shown.
      • If not, rotate crankshaft pulley as shown and align them.
    4. Referring to mating marks on the intake and exhaust camshaft sprockets, put paint mating marks on timing chain links.
    Fig 2: Identifying Mating Marks Stamped On Intake And Exhaust Sprockets
    G00773945Courtesy of NISSAN MOTOR CO., U.S.A.
  4. Set the intake camshaft sprocket to the most advanced position.
    CAUTION: Removal and installation of the intake camshaft sprocket is required to maintain the most advanced position because of the following reasons. Therefore, follow the procedure exactly.
    • Sprocket and vane (camshaft in front) rotate and become offset within the specific angle range.
    • When engine is stationary, the vane is located at the most retarded position. The vane is fixed to the sprocket by an internal lock pin. Therefore, it does not rotate.
    • If the camshaft sprocket mounting bolts are turned under the above circumstance, the lock pin will be damaged by lateral load (shear stress). It may cause non-standard operation.
    NOTE: "Rotating direction" means direction viewed from the engine front side.
    CAUTION: Do not remove the chain tensioner before performing this step.
    Fig 3: Vane Fixed To Sprocket By An Internal Lock Pin
    G00773946Courtesy of NISSAN MOTOR CO., U.S.A.
    1. Using a wrench, hold the hexagonal part so that the intake camshaft does not move.
      Fig 4: Holding Hexagonal Part Of Intake Camshaft Using Wrench
      G00773947Courtesy of NISSAN MOTOR CO., U.S.A.
    2. Using an air gun, apply air pressure to the intake valve timing control solenoid valve advance side oil passage on the top surface of the No. 1 camshaft bracket.
      Fig 5: Applying Air Pressure To Advance Side Oil Passage On Top Surface Of No 1 Camshaft Bracket
      G00773948Courtesy of NISSAN MOTOR CO., U.S.A.
      1. Compressed air pressure :300 kPa (3.06 kg/cm2, 43.5 psi) or more 
      • Keep applying air pressure until step "d" is completed.
      CAUTION:
      • Be careful not to damage the oil passage from interference of the air gun tip.
      • Thoroughly wipe off the oil before applying air pressure. When applying air pressure, cover around the air gun using a rag. Wear protective glasses if necessary.
    3. Slowly turn the intake camshaft in direction A (counterclockwise: intake manifold side).
      • Perform while applying air pressure.
      CAUTION: Be careful not to dislocate the camshaft retaining spanner.
      Fig 6: Applying Air Pressure To Intake Valve Timing Control Solenoid
      G00773949Courtesy of NISSAN MOTOR CO., U.S.A.
    4. During the above step, an operating click (a sound indicating internal lock pin is disengaged) is heard from the inside of the intake camshaft sprocket. After hearing it, slowly turn intake camshaft in direction B (clockwise: exhaust manifold side), and set to most advanced position.
      • Perform while applying air pressure.
      • When the vane rotates solely against sprocket, lock pin is disengaged even if operating click is not heard.
      • If the lock pin is not disengaged, giggle the camshaft with a wrench.
      • If the lock pin is not disengaged with the above step, tap the intake camshaft in front with a plastic hammer.
    5. The following status indicates that the most advanced position is achieved: vane starts rotating on it own, then the sprocket also starts rotating when camshaft is turned. When above status is achieved, this step is complete.
      • The most advanced position is confirmed when the stopper pin groove and lock pin breathing groove are aligned.
      Fig 7: Aligning Stopper Pin Groove And Lock Pin Breathing Groove
      G00773950Courtesy of NISSAN MOTOR CO., U.S.A.
    6. Stop the air and insert stopper pin [approximately 3 mm (0.12 in) dia., length of inserted part is approximately 15 mm (0.59 in)] into pinhole on camshaft sprocket to fix the most advanced position.
      Fig 8: Inserting Stopper Pin
      G00773951Courtesy of NISSAN MOTOR CO., U.S.A.
      CAUTION: Load (spring reaction force) is not applied to stopper pin. Pin is easily detached. Therefore, secure it with vinyl tape to prevent detachment.
      NOTE: In the figure, an Allen wrench [a/f 2.5 mm (0.091 in), short part: approximately 20 mm (0.79 in), long part: approximately 50 mm (1.97 in)] is used for stopper pin as an example.
  5. Remove the chain tensioner.
    1. Press the plate down and release the stopper tab.
    2. Insert the plunger into the tensioner body until it stops.
    3. Secure the plate by passing the stopper pin (such as a hard wire) through the plate hole and body hole. (Plunger is also secured.)
    4. Remove the chain tensioner bolts and remove the chain tensioner.
    Fig 9: Removing Chain Tensioner
    G00773952Courtesy of NISSAN MOTOR CO., U.S.A.
  6. While holding the hexagonal part of the camshaft with a wrench, loosen the intake and exhaust camshaft sprocket bolts and remove the intake and exhaust camshaft sprockets.
    CAUTION:
    • Avoid securing the camshaft at other than the hexagonal part and loosening bolts by utilizing tension of timing chain.
    • After this step is completed, do not rotate crankshaft and camshaft separately in order to prevent interference between the valves and pistons.
    Fig 10: Removing Intake And Exhaust Camshaft Sprocket Bolts
    G00773953Courtesy of NISSAN MOTOR CO., U.S.A.
  7. Handle the intake camshaft sprocket as follows.
    CAUTION:
    • Secure the stopper pin with vinyl tape to prevent detachment.
    • Avoid dropping it or subjecting it to impact.
    • Do not disassemble. (Do not loosen the 3 bolts on front surface.)
    NOTE: If stopper pin is detached and the lock pin is engaged at the most retarded position during removal, recover as follows.
    1. Reinstall the stopper pin to intake camshaft, and tighten the intake camshaft sprocket bolts so that air does not leak.
      CAUTION: Tightening torque for the bolts must be minimum so that air does not leak, preventing damage to the internal lock pin.
    2. Apply air pressure to disengage the lock pin, and turn the vane to the most advanced position. (This step can be performed with the timing chain removed.)
    3. Reinstall stopper pin.
    4. Remove intake camshaft sprocket from the camshaft.
    Fig 11: Reinstalling Stopper Pin To Intake Camshaft
    G00773954Courtesy of NISSAN MOTOR CO., U.S.A.
  8. Loosen the camshaft bracket bolts in the order shown, and remove the camshaft brackets and camshafts.
    CAUTION: Be careful not to damage signal plate on rear end of intake camshaft.
  9. Remove adjusting shims and valve lifters.
    • Note positions, and set them aside in the order removed.
    Fig 12: Identifying Removal Sequence Of Camshaft Bracket Bolts
    G00773955Courtesy of NISSAN MOTOR CO., U.S.A.
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