lubricate plunger with test oil. Install injector spring and
plunger in correct body; check to see that it does not bind
as it seats in cup.
(7) Fill injector body two-thirds full of clean
fuel. Insert plunger forcing fuel out cup spray holes to
see that they are open and clean.
(1) Clean the injector sleeve with a clean
cloth wrapped around a wooden stick. Never use a
Figure 3-88. Size marking location on plunger.
screwdriver or other metal device for this operation; a
scratched injector sleeve may cause a compression
Figure 3-90. Markings on injector cups.
Figure 3-89. Size markings on injector body.
(1) Install new O-ring with proper assembly
(a) Dip O-ring in clean lubricating oil or
(b) Assemble proper tool over threaded end
(c) Slide O-ring over tool into groove.
Select new injector cup gasket
See figure 3-88 for location of size markings on plunger
Figure 3-91. Injector cup wrenches.
(2) Place all injectors in injector bores in
When PT flanged injectors are fitted with
oversize plungers, thicker cup gaskets are used to provide the
Note. When installing injectors in engine, position
original relationship between plunger and metering orifice.
injector plunger so class marks on plunger sleeves are
(3) Install proper cup on injector body finger
centered between fuel connection openings.
Caution: Be careful not to damage injector
Immerse injector plunger in clean
injector test oil and install in body without spring and
(3 ) Start, but do not tighten, hold-down
place injector in ST-569 with correct spacer to align
capscrews into injector mounting holes in cylinder head.
plunger in body. Tighten cup to specified torque with cup
(4) Place new gaskets on fuel inlet and
drain connections; install drain connections in left holes
Note. Two types of injector cup wrenches have been
and inlet connections in right holes of injectors.
used, three spline and six spline, always use the six spline
(5) Start fuel connections into injectors;
Note. Unless proper gasket is used with corresponding
approximately three turns are required to align injector
body and plunger, the engine will develop a miss on cylinder
body with fuel connections.
containing the improperly rebuilt injector.
(6) Tighten injector hold-down capscrews
(5) Check injector assembly plunger seating
with torque wrench in alternate steps to 12 ft.-lbs., figure
on ST-570 or ST-990, preferably ST-990 if available.
(6) Remove injector plunger from body;