Yanmar 3TNV82A Service Manual page 242

FUEL SYSTEM
• Calculate the difference between the timing
index numbers (Figure 7-25, (1)) of the fuel
injection pump that you removed and the
replacement fuel injection pump. See
Calculation Example below.
(1)
Figure 7-25
Adjusting the fuel injection timing to
compensate for the difference in pump timing
index numbers:
Calculation Example
Timing Index Number
Original injection pump= 6.8
Replacement injection pump= 7.3
• If the difference between the timing index
numbers is a positive number, the fuel injection
pump mounting position must be advanced
(Figure 7-26, (2)) (rotated away from the
engine) as compared to the "standard mark"
(Figure 7-26, (1)) by the calculated positive
amount, adjust the fuel injection pump to the
calculated value.
• If the difference between the timing index
numbers is a negative number, the
replacement injection pump must be retarded
(Figure 7-26, (3)) (rotated toward the engine)
by the calculated negative amount.
• Each mark on the timing sticker represents
0.5° timing change.
7-24
0002047
Difference= +0.5
The above calculated difference indicates that
the replacement fuel injection pump is to be
installed at +0.5° (advanced) from the "Standard
Mark" (Figure 7-26, (1)) on the timing sticker.
(3)
+0.5°
+1.0°
(2)
Figure 7-26
In this case, rotate the top of the fuel injection
pump away from the cylinder block until the mark
on the outside upper mounting boss
(Figure 7-27, (1)) of the fuel injection pump
aligns with the +0.5° mark on the timing sticker.
(1)
Figure 7-27
TNV DI Service Manual
Fuel Injection Pump
(1)
0002124A
0002125A