Camshaft Valve Clearance: Inspection
- Intake side:
- At the removal and installation of VVEL ladder assembly or valve-related parts, or at the occurrence of malfunction (poor starting, idle malfunction, unusual noise) due to aged deterioration in valve clearance.CAUTION: Valve clearance check on the intake side is not required when replacing the VVEL ladder assembly & cylinder head assembly with a new one. (Install new VVEL ladder assembly & cylinder head assembly in factory-shipped condition because it is factory-adjusted and inspected.)NOTE: VVEL ladder assembly cannot be replaced as a single part, because it is machined together with cylinder head assembly.
- At the removal and installation of VVEL ladder assembly or valve-related parts, or at the occurrence of malfunction (poor starting, idle malfunction, unusual noise) due to aged deterioration in valve clearance.
- Exhaust side:
- At the removal, installation, and replacement of exhaust camshaft or valve-related parts, or at the occurrence of malfunction (poor starting, idle malfunction, unusual noise) due to aged deterioration in valve clearance.
- Remove VVEL actuator housing assembly. Refer to Removal and Installation .
- Measure the valve clearance as per the following:
- Use a suitable tool with a curved-tip. This allows the suitable tool to access the clearance between camshaft (drive shaft) nose and valve lifter with ease.
Valve clearance
: Refer to Camshaft .
NOTE: Be sure to note the following points when measuring valve clearance on the intake side.- Before measuring, check that the position of drive shaft nose is within the angle shown in the figure, below.
(A)
: Bank 2
(B)
: Suitable tool
(C)
: 45 degrees (drive shaft nose angle)
(D)
: View D
: Insertion direction of feeler gauge on the bank 2
: Insertion direction of feeler gauge on the bank 1
- Refer to the figure for the insertion direction of the suitable tool since the direction depends on the bank.
- Set No. 1 cylinder at TDC of its compression stroke.
- Rotate crankshaft pulley clockwise to align timing mark (grooved line without color) (B) with timing indicator (A).
- Check that exhaust cam nose on No. 1 cylinder (engine front side of bank 1) is located as shown in the figure, below.
(1)
: Exhaust camshaft (bank 1)
: Engine front
- If not, turn crankshaft one revolution (360 degrees) and align as shown in the figure, below.
- By referring to the figure, measure the valve clearances at locations marked "x" as shown in the table below (locations indicated in the figure, below).
: Engine front
- No. 1 cylinder at compression TDC
Measuring position [bank 2 (A)]
No. 2 CYL.
No. 4 CYL.
No. 6 CYL.
No. 8 CYL.
No. 1 cylinder at compression TDC
EXH
x (C)
INT
x (D)
x (E)
Measuring position [bank 1 (B)]
No. 1 CYL.
No. 3 CYL.
No. 5 CYL.
No. 7 CYL.
No. 1 cylinder at compression TDC
INT
x (F)
x (G)
EXH
x (H)
x (I)
NOTE: To measure valve clearance of No. 1 cylinder INT valve (front side), insert suitable tool (A) as shown in the figure, below.: Engine front
- Rotate crankshaft pulley clockwise to align timing mark (grooved line without color) (B) with timing indicator (A).
- Rotate crankshaft clockwise (when viewed from engine front) to align No. 3 cylinder at TDC its compression stroke.NOTE: Crankshaft pulley bolt flange has an angle mark (B) every 90 degrees (c). They can be used as a guide to rotation angle.
(A)
: Paint mark
- By referring to the figure, measure the valve clearances at locations marked "x" as shown in the table below (locations indicated in the figure, below).
: Engine front
- No. 3 cylinder at compression TDC
Measuring position [bank 2 (A)]
No. 2 CYL.
No. 4 CYL.
No. 6 CYL.
No. 8 CYL.
No. 3 cylinder at compression TDC
EXH
x (C)
INT
x (D)
Measuring position [bank 1 (B)]
No. 1 CYL.
No. 3 CYL.
No. 5 CYL.
No. 7 CYL.
No. 3 cylinder at compression TDC
INT
x (E)
x (F)
EXH
x (G)
x (H)
- By referring to the figure, measure the valve clearances at locations marked "x" as shown in the table below (locations indicated in the figure, below).
- Rotate crankshaft clockwise (when viewed from engine front) to align No. 6 cylinder at TDC of compression stroke.NOTE: Crankshaft pulley bolt flange has an angle mark (B) every 90 degrees (c). They can be used as a guide to rotation angle.
(A)
: Paint mark
- By referring to the figure, measure the valve clearances at locations marked "x" as shown in the table below (locations indicated in the figure, below).
: Engine front
- No. 6 cylinder at compression TDC
Measuring position [bank 2 (A)]
No. 2 CYL.
No. 4 CYL.
No. 6 CYL.
No. 8 CYL.
No. 6 cylinder at compression TDC
EXH
x (B)
x (C)
INT
x (D)
- By referring to the figure, measure the valve clearances at locations marked "x" as shown in the table below (locations indicated in the figure, below).
- Use a suitable tool with a curved-tip. This allows the suitable tool to access the clearance between camshaft (drive shaft) nose and valve lifter with ease.
- Perform adjustment or replacement if the measured value is out of the standard.
- If a valve clearance on the exhaust side is out of specification, adjust the valve clearance. Refer to Inspection .
- If a valve clearance on the intake side is out of specification, adjust the valve clearance. Refer to Inspection .