Yanmar 4TNV98, Service Manual

Page: 198 / 246

4TNV98 & 4TNE98 Diesel Engine Section 4. Fuel System 196
Servicing The Fuel Injectors
Removal of the Fuel Injectors
1. Remove the high pressure fuel lines.
Figure 7-50
• First just loosen the high pressure fuel line nuts
(Figure7-50, (2)) at the fuel injectors.
CAUTION
When loosening or tightening the lines at the
fuel injectors, you must hold the fuel injector
with a second wrench to prevent the injector
from turning and damaging the fuel return line
fitting.
• Then loosen the high pressure fuel line nuts
(Figure7-50, (3)) on the fuel injection pump.
• Finish loosening all the high pressure fuel line
nuts and remove the fuel lines as an assembly.
Be careful not to bend any of the fuel lines.
CAUTION
Remove the high-pressure fuel injection lines
as an assembly whenever possible.
Disassembling the high-pressure fuel injection
lines from the retainers or bending any of the
fuel lines will make it difficult to reinstall the
fuel lines.
NOTE: It is necessary to remove the bolt (Figure7-
51, (1)) holding the dipstick tube clamp. Rotate the
dipstick tube to one side to allow you to remove the
high pressure fuel line assembly.
Figure 7-51
2.
Unscrew the fuel injectors from the cylinder head.
Also remove the two copper washers and the
nozzle protectors that will remain in the cylinder
head.