TM 5-3825-225-14&P
Figure 5-41. Fuel Pump Pushrod.
Figure 5-42. Timing Pin .
5-20. TIMING ENGINE.
NOTE
As timing gears are used, the factory setting remains constant. The removal of
the cylinder head does not affect the Injector pump or the valve timing.
a.
Timing Marks.
When the engine is originally timed at the factory, marks are stamped on the gears. If the engine timing is disturbed,
resetting the original timing is quite straightforward.
b.
Resetting Engine to Original Timing (see Appendix E Figures 56 and 58).
CAUTION
Use great care when timing engine. If timing is incorrectly set, even by only one
tooth, a valve head may strike the piston crown when the engine is started.
Damage to engine will result.
(1) Before timing, remove the camshaft (see n above), injector pump (see paragraph 5-22), and idler gears
(see d above). Ensure that the camshaft is free to turn by hand. If the cylinder head assembly is still in
position, remove the atomizers and rocker shaft to facilitate the timing operations.
(2) Turn the engine until the keyway in the front of the crankshaft is up (see Figure 5-42). This will bring no.
1 and no. 4 pistons to TDC.
(3) Install the camshaft gear (3, Appendix F, Figure 58) to its hub ensuring that the "D" marks are correctly
aligned (see Figure 5-33). Secure with the three setscrews (1).
(4) Install the injector pump gear (13) to the injector pump drive hub (11) ensuring that the stamped timing
marks align (see Figure 5-34). Secure with three setscrews (6).
(5) Align the idler gear double dots to the single dot on the crankshaft gear. Align the single line (or dot) on
the camshaft gear and the single dot on the idler gear with the double dots on the injector pump gear.
These timing marks when correctly positioned will appear as shown in Figure 5-42.
(6) Locate the idler gear (15) with the hub (4, Appendix F, Figure 56) and the two securing setscrews (1)
using a new tabwasher (2).
(7) Refer to paragraph 5-19e to adjust.
TA506350
5-30
