Jacobsen SXG323, Service Manual

Page: 39 / 230

SERVICE MANUAL FOR SXG323&326
38
(7) Make sure that fuel ejects from the delivery
holder. Turn the crankshaft slowly in correct
direction (clockwise viewed from the fan) until
fuel ejection stops. The injection timing is just
before fuel ejection stops.
• When fuel ejection stops, the injection timing
point is passed. Turn the crankshaft in reverse
and repeat operation (6).
• Even when the injection timing point is passed,
there is no sign of fuel ejection stopping. The
point is BTDC in exhaust stroke. Turn the crank-
shaft fully by 360" and start operation.
• As a criterion of just before fuel stops," use
the time to take to refill the fuel in the end of the
delivery holder after blowing it off. When it
takes 1 to 2 seconds to refill, it is the fuel injec-
tion timing point.
(8) Check to see the timing mark on the flywheel or
the crankshaft pulley is aligned as shown in
3.2. Adjustment of valve clearance.
For reference:
The crank angle 1
°
is about 1mm on the crank-
shaft pulley and about 2.5 mm on the flywheel.
(9) Turn the key switch to OFF and close the fuel
cock.
(10)After checking to see the fuel injection timing is
correct, remove the delivery holder and install
the delivery spring and stopper. Then re-tighten
the delivery holder to the specified torque.
(11)Install the injection pipe and tighten the nut to
the specified torque.
Note:
-Supply fuel only when fuel injection timing is
measured (only for operation 6)].
-It is impossible to measure the fuel injection tim-
ing by turning the crankshaft in reverse (counter-
clockwise viewed from the fan).
-During this operation, be sure to keep dust out of
the fuel system.
• Adjustment of injection timing
When the injection timing is improper, it should
be corrected.
The injection timing can be adjusted by chang-
ing the distance between the camshaft and
pump-mounting surface with shims.
a. Remove the injection pump cover.
b. Remove
t
he control link and starting spring from
the control rack.
c. Remove the injection pump.
-Shimming
Available adjusting shims: 0.1, 0.2, 0.3, 0.4 and
0.5 mm thick.
For reference:
Injection timing shift with 0.1 mm thick shim-
ming by crank angle:
Sh0.1 mm 1
°
delay
Shimming -0.1 mm 1
°
advance
d. Install the injection pump.
e. Confirm that the injection timing is proper by the
operation mentioned above. Until the proper fuel
injection timing is attained, repeat steps from c. to
e.
f. Install the control link and starting spring on the
control rack and then the injection pump cover.
Note:
During this operation, be careful to keep dust out
of the fuel system.
4IGHTENING TORQUE
KGF ･ M
&IG