Valve Clearance: Testing and Inspection

Valve Clearance Inspection And Adjustment

NOTE:
Inspect and adjust the valve clearance when the engine is cold (Engine coolant temperature : 20°C (68°F)) and cylinder head is installed on the cylinder block.

1. Remove the cylinder head cover (A).
2. 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 chain cover.




B. Check that the mark(A) of the CVVT sprockets are in straight line on the cylinder head surface as shown in the illustration.
If not, turn the crankshaft one revolution (360°)




3. Inspect the valve clearance.
A. Check only the valve indicated as shown. [No. 1 cylinder : TDC/Compression] measure the valve clearance.




-Using a thickness gauge, measure the clearance between the tappet 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 tappet.

Valve clearance
Specification
Engine coolant temperature : 20°C [68°F]
Limit
Intake : 0.10 - 0.30mm (0.0039 - 0.0118in.)
Exhaust : 0.20 - 0.40mm (0.0079 - 0.0157in.)

B. Turn the crankshaft pulley one revolution (360°) and align the groove with timing mark "T" of the lower timing chain cover.
C. Check only valves indicated as shown. [NO. 4 cylinder : TDC/compression]. Measure the valve clearance.




4. Adjust the intake and exhaust valve clearance.
A. Set the No.1 cylinder to the TDC/compression.
B. Marks on the timing chain and camshaft timing sprockets.
C. Remove the service hole bolt(A) of the timing chain cover.





CAUTION:
The bolt must not be reused once it has been assembled.

D. Insert the SST(A) (09240-2G000) in the service hole of the timing chain cover and release the ratchet.




E. Remove the front camshaft bearing cap(A).




F. Remove the exhaust camshaft bearing cap and exhaust camshaft.
G. Remove the intake camshaft bearing cap and intake camshaft.

CAUTION:
When disconnecting the timing chain from the CVVT sprocket, tie or hold the timing chain so it does not fall into the timing chain cover.

H. Tie down timing chain so that it doesn't move.

CAUTION:
Be careful not to drop anything inside timing chain cover.

I. Measure the thickness of the removed tappet using a micrometer.




J. Calculate the thickness of a new tappet so that the valve clearance comes within the specified value.

Valve clearance (Engine coolant temperature : 20°C(68°F))
T : Thickness of removed tappet
A : Measured valve clearance
N : Thickness of new tappet
Intake : N = T + [A - 0.20mm(0.0079in.)]
Exhaust : N = T + [A-0.30mm (0.0118in.)]

K. Select a new tappet with a thickness as close as possible to the calculated value.

NOTE:
Shims are available in 47size increments of 0.015mm (0.0006in.) from 3.00mm (0.118in.) to 3.690mm (0.1452in.)

L. Place a new tappet on the cylinder head.
M. Hold the timing chain, and install the intake camshaft and CVVT assembly.
N. Align the matchmarks on the timing chain and CVVT sprocket.
O. Install the exhaust camshaft and CVVT assembly.
P. Install the front bearing cap.

Tightening torque :
14.7N.m (1.5kgf.m, 10.8lb-ft) + 27.4 - 31.4N.m (2.8 - 3.2kgf.m, 20.3 - 23.1lb-ft)

Q. Install the service hole bolt.

Tightening torque :
11.8 - 14.7N.m (1.2 - 1.5kgf.m, 8.7 - 10.8lb-ft)

R. Turn the crankshaft two turns in the operating direction(clockwise) and realign crankshaft sprocket and camshaft sprocket timing marks(A).




S. Recheck the valve clearance.

Valve clearance (Engine coolant temperature : 20°C(68°F))
[Specification]
Intake : 0.17 - 0.23mm (0.0067 - 0.0090in.)
Exhaust : 0.27 - 0.33mm (0.0106 - 0.0129in.)