FLYWHEEL MARKINGS.
The flywheel markings and timing pointer are visible when the inspection cover on the right-hand side of the flywheel housing is removed.

The markings and their meanings are as follows:
(1) The line against which the letters T.DC. are stamped when brought dead opposite the pointer means that No. 1, piston is on Top .Dead Centre, i.e., at the top of its stroke.

(2) The line against which the letters F.A. are stamped when set opposite the pointer, indicates the firing-point of No. 1 cylinder when the octane selector is set in the standard position on the' sliding scale i.e. the point at which the distributor points should be just opening, with the rotor in the firing position for No. 1 or No. 4 cylinder (" 60 ") or No. 6 cylinder (" 75 ").

(3) The line against which the letters E.P. are stamped, when set opposite the pointer, indicates the point at which No. 1 exhaust valve should be 'at the peak Of its lift (fully open).

VALVE TIMING.
If the timing chain should have been removed, the procedure to re-time the engine is as follows. (See Fig. .23).
(1) Set the tappets as instructed on Page 63.

(2) Rotate the camshaft in the running direction until No. I exhaust valve is fully open.
The use of a dial indicator is the only reliable method of determining this point. It should be mounted on a stud adjacent to No. 1 exhaust rocker and with its aid the possibility of an error in determining the exhaust peak is eliminated. It. is possible to do the job correctly without a dial indicator, but much time is wasted, and the possibilities of an error very much' magnified.

(3) Rotate the engine in the running direction until the E.P. mark on the flywheel is in line with the pointer.

Fig. 23. Timing Gears.
A-Camshaft chainwheel.
B-Crankshaft chainwheel.
C-Jockey pulley.
D-Hydraulic tensioner.
E-Pawl.
F-Ratchet.
G-Timing chain (driving side).

(4) Release the ratchet (E,F) retaining the jockey pulley (c), pull the pulley clear of the chain path and secure in that position with copper wire passed round the end of the jockey pulley shaft.

(5) Fit the timing chain, ensuring that there is no slack on the driving side (G).

(6) Check the timing and correct if necessary. The camshaft, chainwheel (A) is made with three irregularly spaced keyways, so that if the timing will not come correct in the first position tried, alternatives are provided.

(7) Release the jockey pulley and engage it with the timing chain. Ensure that the ratchet (E,F) is engaged.

IGNITION TIMING.
(1) Rotate the engine until the FA mark on the flywheel is in line with the pointer with both valves on No. I cylinder closed.

(2) The rotor of the distributor will now correspond with No. 1 cylinder high tension lead terminal.

(3) Set the octane selector at "0" on the sliding scale.

(4) Set the distributor points just breaking by slackening the 0.25 in. pinch bolt at the base of the distributor head and rotate the distributor bodily in the required direction. Do not forget to, re-tighten the pinch bolt. The correct gap for the points when fully open is .012 in. (0,30 mm.), see Page 74. (Use the combined feeler gauge and screwdriver supplied in the tool tray).

TAPPIT ADJUSTMENT.
The firing order is 1, 3, 4, 2 on "60" and 1, 5, 3, 6, 2, 4 on "75" models.
Adjustment for clearance between the rocker and valve is provided by a set-screw and lock-nut on the rocker. (See Figs. 24 arid 25). When adjustment is required, slacken the lock-nut and rotate the set-screw to give the correct clearance by means of a screwdriver. The lock-nut should be securely tightened after adjustment, great care being taken to ensure that this operation does not upset the clearance.