Use a socket and torque wrench and tighten injector nut to 55-65 lb ft torque.
Do not exceed specified torque. Nut may be stretched and result in improper sealing of the lapped
surfaces in injector.
Plunger and Follower
Invert injector assembly in fixture (filter cap end up), and push rack in all way. Then place follower
spring on injector body.
Refer to Figure 5-10 and place stop pin on the injector body so that tighter wound end of follower
spring rests on narrow flange of stop pin. This end of follower spring has been cut so that end point is to outside. Then,
align slot in follower with stop pin hole in injector body. Next, align flat side of plunger with slot in follower. Then, insert
free end of plunger in injector body. Press down on follower and at same time press stop pin into position. When in
place, spring will hold the stop pin in position.
Check Spray Tip Concentricity. To ensure correct alignment, check concentricity of the spray tip as
Place injector in concentricity gage as illustrated in Figure 5-14 and adjust dial indicator to zero.
Rotate injector to 360° and note total runout as indicated on dial.
If total runout exceeds 0.008 in. remove injector from gage. Loosen injector nut, recenter spray tip,
tighten nut to 55-65 lb ft torque and recheck concentricity.
If after several attempts spray tip cannot be positioned satisfactorily, replace injector nut.
Test Reconditioned Injector
Before placing a reconditioned injector in service, perform all tests except visual inspection of
The injector is satisfactory if it passes these tests. Failure to pass any one of tests indicates that
defective or dirty parts have been assembled.