Valve Clearance: Adjustments
VALVE CLEARANCEADJUSTMENT
HINT: Inspect and adjust the valve clearance when the engine is cold.
1. REMOVE RH ENGINE UNDER COVER
2. REMOVE AIR CLEANER ASSEMBLY
3. REMOVE CYLINDER HEAD COVER
4. SET NO. 1 CYLINDER TO TDC/COMPRESSION
a. Turn the crankshaft pulley, and align its groove with timing mark 0 of the timing chain cover.
b. Check that the timing marks of the camshaft timing sprocket and VVT timing sprocket are aligned with the timing marks of the No. 1 and No. 2 bearing caps as shown in the illustration.
If not, turn the crankshaft 1 revolution (360°) and align the marks as above.
5. INSPECT VALVE CLEARANCE
a. Check only the valves indicated.
1. Using a feeler gauge, measure the clearance between the valve lifter and camshaft.
2. Record the out-of-specification valve clearance measurements. They will be used later to determine the required replacement adjusting valve lifter.
Valve Clearance (cold):
b. Turn the crankshaft 1 revolution (360°) and align the mark as above (see step 4).
c. Check only the valves indicated as shown. Measure the valve clearance (see step (a).
6. ADJUST VALVE CLEARANCE
a. Set the No. 1 cylinder to the TDC/compression (See step 4)
b. Place matchmarks on the timing chain and camshaft timing sprockets.
c. Remove the 2 nuts, gasket and chain tensioner.
d. Hold the hexagonal head portion of the camshaft with a wrench, and loosen the camshaft timing sprocket bolt.
NOTICE: Be careful not to damage the cylinder head and valve lifter with the wrench.
e. Uniformly loosen and remove the 10 camshaft bearing cap bolts in several passes, in the sequence shown.
f. Remove the 5 camshaft bearing caps.
g. Raising the camshaft, remove the camshaft timing sprocket bolt.
h. Disconnect the camshaft timing sprocket together with the timing chain from the exhaust camshaft.
i. Remove the camshaft timing sprocket from the timing chain.
j. Uniformly loosen and remove the 10 camshaft bearing cap bolts in several passes, in the sequence shown.
k Remove the 5 camshaft bearing caps.
l. Disconnect the timing chain from the VVT timing sprocket, and remove the intake camshaft with the VVT timing sprocket.
Tie the timing chain as shown in the illustration.
NOTICE: Be careful not to drop anything inside the timing chain cover.
Do not allow the chain to come into contact with water or dust.
n. Remove the valve lifter.
o. Determine the replacement valve lifter size according to these Formula or Charts:
- Using a micrometer, measure the thickness of the removed lifter.
- Calculate the thickness of a new lifter so the valve clearance comes within the specified value.
T Thickness of used lifter
A Measured valve clearance
N Thickness of new lifter
Intake N = T + (A - 0.24 mm (0.009 inch)
Exhaust N = T + (A - 0.35 mm (0.014 inch)
- Select a new lifter with a thickness as close as possible to the calculated values.
HINT: Valve lifters are available in 35 sizes in increments of 0.020 mm (0.0008 inch), from 5.060 mm (0.1992 inch) to 5.740 mm (0.2260 inch).
Identification number inside the valve lifter shows the value of the 2 decimal places (The illustration shows 5.380 mm (0.2118 inch).
Valve Lifter Selector Chart (Intake):
Valve Lifter Selector Chart (Exhaust):
p. Apply a light coat engine oil to new valve lifter.
q. Reinstall the valve lifter.
r. Align the crankshaft pulley groove with timing mark 0 of the timing chain cover.
s. Hold the timing chain.
7. REINSTALL INTAKE CAMSHAFT
a. Align the matchmarks on the timing chain and VVT timing sprocket (See step 6 (b), and place the intake camshaft on the cylinder head.
b. Apply a light coat engine oil on the threads and under the camshaft bearing cap bolts.
c. Install the 5 intake camshaft bearing caps in their proper locations.
d. Uniformly tighten the 10 bearing cap bolts in several passes, in the sequence shown.
Torque:
30 Nm (301 kgf-cm, 22 ft. lbs.) for bolt A
9.0 Nm (92 kgf-cm, 80 inch lbs.) for others
e. Align the matchmarks on the timing chain and camshaft timing sprocket (See step 6 (b), and install them.
8. REINSTALL EXHAUST CAMSHAFT
a. Temporarily install the camshaft timing sprocket with the timing chain to the exhaust camshaft with the bolt.
b. Place the exhaust camshaft on the cylinder head.
c. Apply a light coat engine oil on the threads and under the camshaft bearing cap bolts.
d. Install the 5 exhaust camshaft bearing caps in their proper locations.
e. Uniformly tighten the 10 bearing cap bolts in several passes, in the sequence shown.
Torque:
30 Nm (301 kgf-cm, 22 ft. lbs.) for bolt A
9.0 Nm (92 kgf-cm, 80 inch lbs.) for others
f. Hold the hexagon head portion of the exhaust camshaft with a wrench, and tighten the bolt.
Torque: 54 Nm (551 kgf-cm, 40 ft. lbs.)
g. Check that the each sprocket aligned with the matchmarks as shown in the illustration.
h. Install the chain tensioner.
i. Recheck the valve clearance (see step 5).
j. Check the valve timing.
9. REINSTALL CYLINDER HEAD COVER
10. REINSTALL AIR CLEANER ASSEMBLY
11. REINSTALL RH ENGINE UNDER COVER