Yanmar 3TNV82A Service Manual page 236

FUEL SYSTEM
16. To position the fuel injection pump for easier
removal and installation, install a dial indicator
(see Checking and Adjusting Fuel Injection
Timing on page 7-26) into the injection pump
plunger opening. Using a wrench on the
crankshaft pulley bolt, rotate the crankshaft until
the dial indicator shows that injection pump
plunger is at the bottom of it's stroke.
17. To aid in reassembly, make reference marks on
the fuel injection pump drive gear, and on either
the gear case cover or idler gear.
CAUTION
After marking the position of the pump
drive gear, do not rotate the engine
crankshaft. Rotating the crankshaft will
cause the fuel injection pump to become
misaligned.
• On TNV82-88 model engines, the idler gear is
not visible. Make a reference mark on the fuel
injection pump drive gear (Figure 7-10, (1))
and a matching mark on the bore of the gear
case opening (Figure 7-10, (2)).
(1)
Figure 7-10
7-18
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18. Do not loosen or remove the four bolts
(2)
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• On TNV94 - 106 model engines, the idler gear
is visible. Make a reference mark
(Figure 7-11, (1)) across both the fuel injection
pump drive gear and the idler gear.
Figure 7-11
CAUTION
Do not loosen or remove the four bolts
retaining the fuel injection pump drive
gear to the fuel injection pump hub. Do
not disassemble the fuel injection pump
drive gear from the hub. Correct fuel
injection timing will be very difficult or
impossible to achieve.
(Figure 7-12, (3)) retaining the pump drive gear
to the hub. Only remove the single drive gear
nut (Figure 7-12, (1)) and washer
(Figure 7-12, (2)), leaving the hub attached to
the gear.
TNV DI Service Manual
Fuel Injection Pump
(1)
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