| TIBURON(GK) >2004 > G 2.0 DOHC > Engine Mechanical System > Cylinder Head Assembly > Camshaft>Repair procedures |

DISASSEMBLY
1. | Disconnect the breather hose and the P.C.V. hose.
2. | Remove the coolant pump pulley and crankshaft pulley.
3. | Remove the timing belt cover.
4. | Loosen the timing belt tensioner pulley and temporarily secure it.
5. | Remove the timing belt from the camshaft sprocket.
6. | Remove the ignition coil assembly.
7. | Loosen the cylinder head cover bolts and then remove the cylinder head cover.
8. | Remove the camshaft sprocket.
9. | Remove the camshaft bearing caps and timing chain.
10. | Remove the camshaft.
11. | Remove the mechanical tappets and shims.
Arrange the mechanical tapets and shims in correct order.
12. | Remove the OCV (Oil control valve).
13. | Remove the OCV filter
INSPECTION
1. | Check the camshaft journals for wear. If the journals are badly worn, replace the camshaft.
2. | Check the cam lobes for damage. If the lobe is damaged or worn excessively, replace the camshaft.
Cam height W/O - CVVT [Standard value] Intake : 44.820 mm (1.7646 in.) Exhaust : 44.720 mm (1.7606 in.) [Limit] Intake : 44.720 mm (1.7606 in.) Exhaust : 44.620 mm (1.7567 in.) W - CVVT [Standard value] Intake : 44.618mm (1.7566in.) Exhaust : 44.518mm (1.7527in.) [Limit] Intake : 44.518mm (1.7527in.) Exhaust : 44.418mm (1.7587in.)
3. | Check the cam surface for abnormal wear or damage, and replace if necessary.
4. | Check each bearing for damage. If the bearing surface is excessively damaged, replace the cylinder head assembly or camshaft bearing cap, as necessary.
Camshaft end play : 0.1 ~ 0.2 mm (0.004 ~ 0.008 in.)
CVVT ASSEMBLY
1. | Inspect CVVT assembly.
(1) | Check that the CVVT assembly will not turn.
(2) | Apply vinyl tape to all the parts except the one indicated by the arrow in the illustration.
(3) | Wind tape around tip of the air gun and apply air of approx. 100kpa (1kgf/cm², 14psi) to the port of the camshaft. (Perform this order to release the lock pin for the maximum delay angle locking.)
When the oil splashes, wipe if off with a shop rag and the likes.
(4) | Under the condition of (3), turn the CVVT assembly to the advance angle side (the arrow markded direction in the illustration) with your hand. Depending on the air pressure, the CVVT assembly will turn to the advance side without applying force by hand. Also, under the condition that the pressure can be hardly applied because of the air leakage from the port, there may be case that the lock pin could be hardly released.
(5) | Except the position where the lock pin meets at the maxuimum delay angle, let the CVVT assembly turn back and forth and check the movable range and that there is disturbance.
Standard : Movable smoothly in the range about 20°
(6) | Turn the CVVT assembly with your hand lock it at the maximum delay angle position.
CAMSHAFT OIL SEAL
1. | Check the lips for wear. If the lip threads are worn, replace.
2. | Check the oil seal lip contacting surface of the camshaft. If it is worn, replace the camshaft.
MLA (MECHANICAL LASH ADJUSTER) VALVE CLEARANCE INSPECTION AND ADJUSTMENT
Inspect and adjust the valve clearance when the engine is cold (Engine coolant temperature : 20°C) and cylinder headis installed on the cylinder block.
1. | Remove the engine cover.
2. | Remove the upper timing belt cover.
A. | Loosen the upper timing belt cover bolts and then remove the cover.
3. | Remove the cylinder head cover.
A. | Disconnect the spark plug cables and do not pull on the spark plug cables by force.
Pulling on or bending the cables may damage the conductor inside.
B. | Disconnect the P.C.V. hose and the breather hose from the cylinder head cover.
C. | Disconnect the accelerater cable from the cylinder head cover.
D. | Loosen the cylinder head cover bolts and then remove the cover and gasket.
4. | Set No.1 cylinder to TDC/ compression.
A. | Turn the crankshaft pulley and align its groove with the timing mark "T" of the lower timing belt cover.
B. | Check that the hole of the camshaft timing pulley is aligned with the timing mark of the bearing cap. If not, turn the crankshaft one revolution(360°)
5. | Inspect the valve clearance.
A. | Check only the valves indicated as shown. [No.1 cylinder : TDC/Compression] measure the valve clearance
• | Using a thickness gauge, mesure the clearance between the tappet shim and the base circle of camshaft.
• | Record the out-of-specification valve clearance measurements. They will be used later to determine the required replacement adjusting shim.
Valve clearance [Specification] Engine coolant temperature : 20°C (68°F) Intake : 0.20mm (0.0079 in.) Exhaust : 0.28mm (0.0110 in.) Engine coolant temperature : 80°C (176°F) Intake : 0.29mm (0.0114in.) Exhaust : 0.34mm (0.0134in.) Limit Intake : 0.12 ~ 0.28 mm (0.0047 ~ 0.0110 in.) Exhaust : 0.20 ~ 0.38 mm (0.0079 ~ 0.0150 in.)
B. | Turn the crankshaft pulley one revolution (360°) and align the groove with timing mark "T" of the lower timing belt cover.
C. | Check only the valves indicated as shown. [NO.4 cylinder : TDC/compression]. Measure the valve clearance. (See procedure in step (6))
6. | Adjust the intake and exhaust valve clearance.
A. | Turn the crankshaft so that the cam lobe of the camshaft on the adjusting valve is upward.
B. | Using the special tool (09220-2D000), press down the valve lifter and place the stopper between the camshaft and valve lifter and remove the special tool.
C. | Remove the adjusting shim with a small screw driver and magnet.
D. | Measure the thickness of the removed shim using a micrometer.
E. | Caculate the thickness of a new shim so that the valve clearance comes within the specified value.
Valve clearance (Engine coolant temperature : 20°C) T : Thickness of removed shim A : Measured valve clearance N : Thickness of new shim Intake : N = T + [A - 0.20 mm (0.0079 in.)] Exhaust : N = T + [A - 0.28 mm (0.0110 in.)]
F. | Select a new shim with a thickness as close as possible to the caculated value. [Refer to the Adjusting shim selection chart]
Shims are available in 20 size increments of 0.04 mm (0.0016 in.) from 2.00 mm (0.079 in.) to 2.76 mm (0.1087 in.)
G. | Place a new adjusting shim on the valve lifter.
H. | Using the special tool (09220 - 2D000), press down the valve lifter and remove the stopper.
I. | Recheck the valve clearance.
Valve clearance (Engine coolant temperature : 20°C) [Specification] Intake : 0.20 mm (0.0079 in.) Exhaust : 0.28 mm (0.0110 in.) [Limit] (After adjusting valve clearance) Intake : 0.17 ~ 0.23 mm (0.0067 ~ 0.0091 in.) Exhaust : 0.25 ~ 0.31 mm (0.0098 - 0.0122 in.)
REASSEMBLY
1. | Install OCV filter.
Tightening torque 41 ~ 51Nm (410 ~ 510kgf.cm, 30 ~ 37lbf.ft)
Always use a new OCV filter gasket keep clean the OCV filter.
2. | Install OCV.
Tightening torque 10 ~ 12Nm (100 ~ 120kgf.cm. 7.3 ~ 8.816lbf.ft)
• | Do not reuse the OCV when dropped.
• | Keep clean the OCV.
• | Do not hold the OCV sleeve during servicing.
• | When the OCV is installed on the engine, do not move the engine with holding the OCV yoke.
3. | Install the camshaft.
(1) | Align the camshaft timing chain with the intake timing chain sprocket as shown.
(2) | Install the camshafts and bearing caps.
Tightening torque 14 ~ 15Nm (140 ~ 150kgf.cm, 10 ~ 11lbf.ft)
(3) | Install the timing chain auto tensioner.
(4) | Remove the auti tensioners stopper pin.
4. | Check and adjust valve clearance.
5. | Using the SST (09221-21000), install the camshaft bearing oil seal.
6. | Install the camshaft sprocket.
7. | Install the timing belt.
8. | Install the cylinder head cover.
(1) | Install the cylinder head cover gasket in the groove of the cylinder head cover.
• | Before installing the head cover gasket, thoroughly clean the head cover gasket and the groove.
• | When installing, make sure the head cover gasket is seated securely in the corners of the recesses with no gap.
(2) | Apply liquid gasket to the head cover gasket at the corners of the recess.
• | Use liquid gasket, loctite No. 5999.
• | Check that the mating surfaces are clean and dry before applying liqued gasket.
• | After assembly, wait at least 30 minutes before filling the engine with oil.
(3) | Install the cylinder head cover with the 12 bolts. Uniformly tighten the bolts in several passes.
Tightening torque 8 ~ 10Nm (80 ~ 100kgf.cm, 6 ~ 7.4lbf.ft)
9. | Connect the accelerater cable.
10. | Connect the PCV hose and the breather hose to the cylinder head cover.
11. | Connect the spark plug calbes to the spark plugs.
12. | Install the upper timing belt cover with the four bolts.
13. | Install the engine cover.