Perkins 4.99 - SECTION K Timing; General Timing Information and Marks

K1
General
As timing gears are employed, the factory setting
remains constant. It is also worth remembering that
the removal of the cylinder head in no way effects
either the fuel pump or the valve timing.
TIMING MARKS
When the engine is originally timed at the factory,
certains marks are stamped on the gears, so that if for
any reason the engine timing has to be disturbed, then
to reset to the original timing is quite straight forward.
To Reset the Engine to the Original Timing
Before commencing the retiming procedure it is
assumed
that (a) the camshaft, fuel pump and idler
gears have all been removed, and (b) the camshaft is
free
to turn by hand. (If the cylinder head assembly is
still in position, it is advisable to remove the atomisers
and rocker shaft to facilitate the retiming operations).
1. Turn the engine until the keyway in the front of the
SECTION K
Timing
crankshaft is uppermost as shown in Fig. K.1.
(This will bring Nos. 1 and 4 pistons to T.D.C.)
2. Fit the camshaft gear to its hub ensuring that the
'D' marks are correctly aligned. (Refer to Fig. J.5).
Secure with the three setscrews.
3. Similarly, fit the fuel pump gear to the fuel pump
drive hub ensuring that the stamped timing marks
align as shown in Fig. J.6. Secure with the three
setscrews.
4. Replace the idler gear so that the double dots on
thE; idler gear are matched to the single dot on the
crankshaft gear and single line (or dot) on the
camshaft gear, whilst the single dot on the idler
gear matches with the double dots on the fuel
pump gear. These timing marks when correctly
positioned will appear as shown in Fig. K.1.
5. Locate the idler gear with the hub and the two
securing setscrews using a new tabwasher.
6. Backlash adjustment should be carried out as
described under the heading 'To Refit the Idler
Gear and Hub. (See Page J.1).