2.1.1
Fuel Injector
DETROIT DIESAL 53
Fig. 43. - Relationship Between Exhaust Valve Bridge and Valve Stems
(Fig. 39.). Tighten the nut as tight as possible by hand.
2. Place a new seal ring on the shoulder of the body.
At this point there should be sufficient force on the spray
Then place the spill deflector over the barrel of the
tip to make it impossible to turn with your fingers.
bushing.
8. Use socket J 4983-01 and a torque wrench to
3. Place the check valve centrally on the top of the
tighten the injector nut to 75-85 lb-ft torque (Fig. 40.).
bushing. Then place the check valve cage over the
check valve and against the bushing.
NOTE: Do not exceed the specified
4. Insert the spring seat in the valve spring, then insert
torque. Otherwise, the nut may be
the assembly into the spring cage, spring seat first.
stretched and result in improper
sealing of the lapped surfaces in a
5. Place the spring cage, spring seat and valve spring
subsequent injector overhaul.
assembly (valve spring down) on top of the check valve
cage.
ASSEMBLE PLUNGER AND FOLLOWER
6. Insert the needle valve, tapered end down, inside of
1. Refer to Figs. 24. and 37. and slide the head of the
the spray tip (Fig. 1.). Then place the spray tip and
plunger into the follower.
needle valve on top of the spring cage with the quill end
of the needle valve in the hole in the spring cage.
2. Invert the. injector in the assembly fixture (filter cap
end up) and push the rack all the way in. Then place
7. Lubricate the threads in the injector nut and
the follower spring on the injector body.
carefully thread the nut on the injector body by hand.
Rotate the spray tip between your thumb and first finger
3. Refer to Fig. 41. and place the stop pin on the
while threading the nut on the injector body
injector body so that the follower spring rests on the
narrow flange of the stop pin. Then align the slot in the
follower with the stop pin hole in the injector body. Next
align the flat side of the plunger with the slot in the
follower. Then insert the free end of the plunger in the
injector body. Press down on the follower and at the
same time press the stop pin into position. When in
place, the spring will hold the stop pin in position.
1972 General Motors Corp.
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