TM 5-3825-225-14&P
c.
Checking Valve Timing.
NOTE
A timing pin is fitted at the bottom of the timing case cover on the left side. When
it is unscrewed, it locates in a hole machined in the rear face of the crankshaft
pulley (see Figure 5-42), when no. 1 and no. 4 pistons are at TDC. With some
applications, two holes are provided in the rear face of the crankshaft pulley, i.e.,
one for the TDC position and the other for the static injector pump timing
position. Always return this pin to its normal location immediately after TDC has
been determined and before any attempt is made to turn or start the engine.
(1) Turn the crankshaft until the valves of no. 4 cylinder are on overlap.
(2) In this position, set the valve clearance of no. 1 inlet valve to 0.039 in. (0.99 mm).
(3) Turn the engine slowly in the normal direction of rotation until the clearance of no. 1 inlet valve is just
taken up. It will just be possible to rotate no. 1 inlet valve pushrod between the thumb and the
forefinger.
(4) If the timing has been correctly set, no. 1 and no. 4 pistons will now be at TDC.
NOTE
No adjustment is provided for valve timing. If timing is incorrect and the camshaft
gear has been correctly fitted to the camshaft hub, the error will probably be due
to incorrect alignment of the original timing marks on the drive gears. Recheck
(see b above).
(5) When valve timing is originally set and checked during production, a timing tolerance of 2 1/2°
(flywheel) is allowed for step (4)-above. When the timing has been correctly set, do not forget to reset
no. 1 inlet valve clearance to the correct amount. Also return the timing pin to its correct location if it
has been used to check TDC.
5-21. OIL PUMP MAINTENANCE.
NOTE
The oil pump fits Into a machined bore in the cylinder block and is located by
means of a screw locked by a tabwasher. The oil pump is driven through spiral
gears from the camshaft. On the other end of the drive shaft Is a four-lobed rotor.
This rotor drives a five-lobed rotor that is free to rotate within the pump body.
a.
Oil Pan Removal (See Appendix F, Figure 51).
(1) Remove the oil pan drain plug (14) and drain the oil.
(2) Remove the dipstick (2), oil pan retaining setscrews (18), and oil pan (1) Remove gaskets (4 and 6) and
discard.
b
Oil Pan Installation (see Appendix E Figure 51).
NOTE
When the gaskets are being positioned, the mitered ends must go right up into
the recesses in the front and rear main bearing caps.
(1) Lightly apply a coating of a suitable jointing compound to the crankcase and oil pan faces. Position new
gaskets (4) so that all the holes align.
(2) Lightly apply gasket compound to new gaskets (6). Press gaskets into the grooves provided in the main
bearing caps.
(3) Place the oil pan (1) in position and fit all the retaining setscrews (8). Tighten evenly.
(4) Install the dipstick (2) and oil pan drain plug (14), then refill with clean, new oil (see Chapter 3, Section I).
c.
Oil Pump Removal (See Appendix Figures 59 and 60).
(1) Drain the engine oil and remove oil pan (see a above).
(2) Remove the strainer (7, Appendix F, Figure 60) from the end of the suction pipe (see Figure 5-43).
(3) Unscrew the delivery pipe securing nut (9, Appendix F, Figure 59) to the cylinder block and the setscrew
(4, Appendix F, Figure 60) securing the suction pipe to the rear main bearing cap.
(4) Tap back the tabwasher (7, Appendix F, Figure 59) locking the locating screw (6) and support the oil
pump (1) (if the engine is the normal way up), while the locating screw is removed. Discard tabwasher.
(5)
Remove the oil pump (1) from the cylinder block (see Figure 5-44).
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