DETROIT DIESEL 53
Fuel Injector 2.1.1
attempts, the spray tip cannot be positioned satisfacto-
3. Install the injector clamp, special washer (with
rily, replace the injector nut.
curved side toward injector clamp) and bolt. Tighten
the bolt to 20-25 lb-ft torque. Make sure that the
clamp does not interfere with the injector follower
spring or the exhaust valve springs.
Test Reconditioned Injector
Before placing a reconditioned injector in service,
NOTE: Check the injector control rack for free
perform all of the tests (except the visual inspection of
movement. Excess torque can cause the control
the plunger) previously outlined under Test Injector.
rack to stick or bind.
The injector is satisfactory if it passes these tests.
4. Move the rocker arm assembly into position and
Failure to pass any one of the tests indicates that
secure the rocker arm brackets to the cylinder head by
defective or dirty parts have been assembled. In this
tightening the bolts to the torque specified in
case, disassemble, clean, inspect, reassemble and test
Section 2.0.
the injector again.
CAUTION: On four valve cylinder heads, there
is a possibility of damaging the exhaust valves
Install Injector
if the exhaust valve bridge is not resting on the
ends of the exhaust valves when tightening the
Before installing an injector in an engine, remove the
rocker shaft bracket bolts. Therefore, note the
carbon deposits from the beveled seat of the injector
position of the exhaust valve bridge (Fig. 43)
tube in the cylinder head. This will assure correct
before, during and after tightening the rocker
alignment of the injector and prevent any undue
shaft bolts.
stresses from being exerted against the spray tip.
5. Remove the shipping caps. Then install the fuel
Use injector tube bevel reamer J 5286-9, Section 2.1.4,
pipes and connect them to the injector and the fuel
to clean the carbon from the injector tube. Exercise
connectors. Use socket J 8932-01 to tighten the
care to remove ONLY the carbon so that the proper
connections to 12-15 lb-ft torque.
clearance between the injector body and the cylinder
head is maintained. Pack the flutes of the reamer with
CAUTION: Do not bend the fuel pipes and do
grease to retain the carbon removed from the tube.
not exceed the specified torque. Excessive
tightening will twist or fracture the flared end
Be sure the fuel injector is filled with fuel oil. If
of the fuel line and result in leaks. Lubricating
necessary, add clean fuel oil at the inlet filter cap until
oil diluted by fuel oil can cause serious damage
it runs out of the outlet filter cap.
to the engine bearings.
Install the injector in the engine as follows:
6. Perform a complete engine tune-up as outlined in
Section 14. However, if only one injector has been
1. Refer to Fig. 6 and insert the injector into the
removed and replaced and the other injectors and the
injector tube with the dowel pin in the injector body
governor adjustment have not been disturbed, it will
registering with the locating hole in the cylinder head.
only be necessary to adjust the valve clearance and
time the injector for the one cylinder, and to position
2. Slide the injector rack control lever over so that it
registers with the injector rack.
the injector rack control lever.
SEC. 2.1.1 Page 21
March, 1973
