Sovereign L6-4.0L (1991)
- Fit No 1 cap. Fit but do not tighten the cap securing bolts.
- Remove No 7 cap cylinder head bolt.
- Remove the spacer tool.
- Fit No 7 cap. Fit but do not tighten the cap securing bolts.
- Finally tighten Nos 1 and 7 cap securing bolts in sequence.
- Remove No 4 cap cylinder head bolt and remove the spacer tool.
- Lubricate and fit No 4 cap.
- Fit and tighten No 4 cap securing bolts.
- Fit and tighten No 4 cap cylinder head bolt.
- Repeat the procedure for Nos 2, 3, 5 and 6 caps, LH camshaft.
- Set the LH camshaft to TDC.
- Repeat the procedure for the RH camshaft.
- Rotate the engine as necessary to measure the valve clearances between the heel of the camshaft and the cam followers.
- The correct clearance is 0.012 to 0.014 in.
- Make note of each clearance measurement.
- Should the clearances be incorrect, proceed as follows: Rotate the engine and set number 1 cylinder at TDC using Service Tool 18G 1433.
- Remove the cylinder head bolt from No 2 cap, LH camshaft (1).
- Remove the cap securing bolts from No 2 cap, LH camshaft.
- Remove No 2 cap from the LH camshaft.
- Fit spacer tool 18G 1435 (2) to the head. Fit and torque tighten the cylinder head bolt.
- Repeat the procedure for Nos 3, 4, 5 and 6 caps, LH camshaft (3).
- Remove the cylinder head bolt from No 7 cap, LH camshaft.
- Remove alternately the securing bolts from Nos 1 and 7 caps, until the LH camshaft is free.
- Lift the camshaft from the cylinder head, and fit spacer tool 18G 1435 to No 7 cylinder head bolt position (5). Fit and torque tighten the bolt.
- Repeat the procedure for the RH camshaft.
Valve Clearance Calculation
- Remove all the shims, or only those requiring adjustment, check the size of the existing shims with a micrometer and note the reading.
- Calculate the size of the shim required following the examples below.
VALVE CLEARANCES
Inlet and Exhaust ......................................................................................................................................................................................... 0.012-0.014in
EXCESSIVE CLEARANCE - EXAMPLE
Size of existing shim
0.100
Plus the actual clearance noted
0.019
= 0.119
Less the specified valve clearance
0.013
Equals required shim size
0.106
INSUFFICIENT CLEARANCE - EXAMPLE
Size of existing shim
0.107
Plus the actual clearance noted
0.010
= 0.117
Less the specified valve clearance
0.013
Equals required shim size
0.104
Letter
Thickness
A
0.085 in
B
0.086 in
C
0.087 in
D
0.088 in
F
0.089 in
G
0.089 in
H
0.090 in
I
0.091 in
J
0.094 in
K
0.095 in
L
0.096 in
M
0.097 in
N
0.098 in
0
0.099 in