OM673L3 5/21
17
Servicing
SP-4. AIR CLEANER
1. Inspect air cleaner every 200 hours. In dusty
conditions check more often.
2. Inspect the element. If it is dirty, wash the element
in soapy water. Rinse and dry thoroughly before
re-installing. Replace if necessary. Part number is:
M673L3 & LD3 - #24-28003
NOTE: Failure to change air cleaner at recommended
times can cause severe engine damage. Change
every 1000 hours or two years, whichever comes
first.
NOTE:
Make absolutely sure no impurities enter the
engine while changing the element. Do NOT run the
engine with the air cleaner removed.
SP-5. V-BELTS
1. Check the tension and wear on the V-belt daily.
2. Use your thumb to press on the belt at the midpoint
between the crankshaft and alternator pulleys. The
tension is correct if the belt can be depressed about
3/16 in. (5 mm).
Figure 10:
Valve Adjustment
SP-6. VALVE CLEARANCES
1. Adjust valve clearance every 1000 hours.
2. To bring the No. 1 cylinder to top dead center in the
compression stroke, align the timing mark; the top
mark of the crank pulley with that of the timing gear
case. Remove the rocker arm cover and turn the
crankshaft foward and backward. If the inlet and
exhaust valves of the No. 1 cylinder do not move it is
in top dead center position. When the valves move,
or rock, turn the crankshaft one full turn and align the
top mark of the crank pulley with the top mark of the
timing gear case.
3. Loosen the lock nut and adjust the clearance between
the rocker arm and valve guide of both the intake and
exhaust valves with the adjustment screw (
Figure 10
).
Clearance on both intake and exhaust valves should be
0.008 in. (0.2 mm).
4. Repeat steps 3 and 4 for each cylinder. Each set of
valves must be adjusted individually.
5. Replace the rocker arm cover. Tighten cover nuts to
5 - 8 ft/lbs (0.8 - 2.3 kg/m).
Figure 11:
Timing Mark
Cylinder No. 1 2 3
Valve Arrangement Int. Exh. Int. Exh. Int. Exh.
When No.1 cylinder
is at Top Dead Center
in the compression
stroke
With the crankshaft
turned 360
0
in
normal direction from
above
Valve Arrangement
Updated 8-7-19
