TRUCK SERVICE MANUAL
Note: Do not remove adjustable orifice plug from
Cleaning and Repair
1. Clean injector parts thoroughly of any carbon varnish
by soaking in a solvent such as "Bendix Metal
5. Insert injector into loading fixture.
Cleaner," "Kelite Formula 1006" or equivalent. Ultra-
sonic cleaning in service tool 3375000 is
6. Slide 3375102, Body Wrench, over flats on injector.
recommended for barrel, plunger and cup.
Place ST-995, Retainer Wrench, on injector.
2. Neutralize solvent after cleaning by dipping parts in
7. Activate air cylinder or tighten special screw to hold
3. Dry with clean compressed air.
injector in place. Loosen cup retainer but do not
Caution: Do not use drills or other instruments to
remove. Fig. 6-1-9.
clean cup holes that will alter size of holes. Wires
may be used if a smaller size wire is used than the
8. Deactivate air cylinder or loosen special screw.
4. A clean shop; clean tools and good cleaning
practices are essential to good injector repair. Most
injector failures occur because of dirt. Clean all
parts before assembly.
PT (type D) Injectors Plunger Link
Replace plunger link if worn excessively. See Fig. 6-1-
Fig. 6-1-9, F60197. Loosening cup retainer
9. Remove injector clamp and ST-995 from fixture.
10. Another method of loosening retainer is to use a 1-
¼ inch box or open end wrench on ST-995 and a 1
inch wrench or injector.
Fig. 6-1-23, F60188. Plunger link wear
11. Screw off cup retainer and remove cup, barrel and
discard gasket. DO NOT LOSE CHECK BALL.
1. Check closely for metal seizure. As a rule this is the
only true indication of scuffing or scoring.
12. Remove check ball from top of barrel. Fig. 6-1-10.
2. Bright spots or surface disruption at top of machined
area plunger, on opposite side at bottom of plunger
or at mid-point, usually are normal results of rocker
lever thrust action. Unless metal is displaced or
wear is measurable at these points, the plunger may
be reused. If worn excessively return barrel and
plunger to a Cummins Rebuild Station for fitting of a
3. Narrow streaks running the length of the plunger
usually are the result of the varying thickness of
penetrant treatment used to prevent rusting. Plunger
is satisfactory for reuse unless a surface disruption is
4. Check area where plunger is swaged to coupler for
Fig. 6-1-10, F60190. Removing check ball
cracks and looseness, by attempting to rotate by
5. Excessive wear or fretting may be found on spring
contact area of coupling flange.