Fuel Injector
2.1.1
DETROIT DIESEL 53
Fig. 35 - Details of Injector Filters and Caps
and Their Relative Location
Inspect both ends of the spill deflector for sharp edges
or burrs which could create burrs on the injector body
or injector nut and cause particles of metal to he
introduced into the spray tip and valve parts. Remove
burrs with a 500 grit stone.
Inspect the follower spring for visual defects. Then
check the spring with spring tester J 9666 and an
accurate torque wrench.
Fig. 36 - Injector Rack, Gear, Spray Tip and
Valve Assembly Details and Relative Location
The current injector follower spring (.142 " diameter
of Parts
wire) has a free length of approximately 1.504 " and
should be replaced when a Ioad of less than 70 Ibs. will
surface at this point will result in high fuel
compress it to 1.028 "
consumption and contamination of the lubricating oil.
Replace any loose injector body plugs or a loose dowel
It is recommended that at the time of overhaul, all
pin. Install the proper number tag on a service
injectors in an engine he converted to the current
replacement injector body.
spring (.142 " diameter wire) which will provide
improved cam roller to shaft follow However, in the
event that one or two injectors are changed. the
Inspect the injector plunger and hushing for scoring.
remdining injectors need not be reworked to
erosion, chipping or wear. Check for sharp edges on
incorporate the current spring.
that portion of the plunger which rides in the gear.
Remove any sharp edges with a 500 grit stone. Wash
Check the seal ring area on the injector body for burrs
the plunger after stoning it. Injector Bushing
or scratches. Also check the surface which contacts the
Inspectalite J 21471 can be used to check the port
injector bushing for scratches, scuff marks, or other
holes in the inner diameter of the bushing for cracks
damage. If necessary, lap this surface. A faulty sealing
or chipping. Slip the plunger into the bushing and
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