Thermo King MD-MT, Operator'S Manual

Page: 96 / 192

Engine Maintenance
96
1. Rotate the engine in the direction of rotation
(clockwise as viewed from the water pump
end) until the number 1 cylinder (closest to
flywheel) is at approximately top dead center
of the compression stroke. The valve cover
should be removed to identify the
compression stroke. Both rocker arms of the
number 1 cylinder will be loose. Check to see
that the number 1 cylinder top dead center
mark on the flywheel is aligned with the
timing mark on the starter mounting plate.
NOTE: The timing marks for each of the
three cylinders are stamped 120 degrees
apart. Top dead center marks are identified
by the number of the cylinder stamped next
to them. Injection timing marks are
unmarked. The timing marks on the TK 3.74
engine can be difficult to align. This is
because the timing mark on the starter
mounting plate is near the air cleaner, on the
side of the plates that faces the flywheel. It
cannot be seen when looking through the
curbside door opening unless you use a
mirror.
The timing mark on the starter mounting
plate is a line stamped on the side of the plate
facing the flywheel. To locate the timing
mark, feel the back side of the plate 0.4 in.
(10 mm) below the center of round notch in
the edge of the plate. To make it easier to
align the timing marks, file a V-notch in the
edge of the plate in line with the timing mark
on the plate. Units manufactured after
3-15-89 will have this V-notch in the edge of
the plate.
2. Remove the injection line from the number 1
injector and the injection pump. Remove the
delivery valve holder, delivery valve and
spring. Care must be taken to prevent dirt
from entering the fuel injection system.
Replace the delivery valve holder and delivery
valve.
3. Install a drip valve on the nozzle holder.
4. Activate the run solenoid and the fuel pump
by turning the unit switch On. Make sure the
Diesel/Electric switch is in the Diesel
position.
5. The engine should be close to the top dead
center position with the plunger port in the
pump closed. No fuel should flow from the
drip tube.
6. Turn the engine backwards past the injection
timing mark until fuel flows from the drip
tube.
7. Slowly rotate the engine in the direction of
rotation while watching the drip tube. When
the fuel flow slows to approximately one drip
every 10 to 15 seconds, check the timing
marks. They should be lined up.
8. If the timing marks did not line up, a shim or
shims will have to be added or subtracted
from the injection pump. Adding shims will
retard the injection timing, subtracting shims
will advance the timing. Increasing or
decreasing shim thickness by 0.004 in.
(0.1 mm) will change the timing by 1 degree.
9. After shims have been added or subtracted,
recheck the timing.
CAUTION: The cylinders on the engine
are numbered from the flywheel end to the
water pump end. The number 1 cylinder is
next to the flywheel. The number 2
cylinder is the center cylinder. The
number 3 cylinder is next to the water
pump. The timing marks on the flywheel
are matched to this system.
CAUTION: The 8S wire on the starter
motor should be disconnected.
CAUTION: Loosen the injection lines on
the injection nozzles of the number 2 and
3 cylinders to prevent any possibility of the
engine firing.