TM 5-3810-300-24&P-3
Fuel Injector
2.1.1
NOTE: Immediately after removal of the
TEST INJECTOR
fuel pipes from an injector, cover the
filter caps with shipping caps to prevent
WARNING: The fuel spray from an
dirt from entering the injector. Also
injector can penetrate the skin. Fuel oil
protect the fuel pipes and fuel
which enters the blood stream can
connectors from entry of dirt or foreign
cause a serious infection. Therefore,
material.
follow instructions and use the proper
equipment to test an injector.
3. Crank the engine to bring the outer ends of the push
rods of the injector and valve rocker arms in line
If inspection does not reveal any external damage, then
horizontally.
perform a series of tests to determine the condition of
the injector to avoid unnecessary overhauling. Tests
4. Remove the two rocker shaft bracket bolts and swing
must be performed using injector test oil J 26400.
the rocker arms away from the injector and valves (Fig.
An injector that passes all of the tests outlined below
may be considered to be satisfactory for service without
5. Remove the injector clamp bolt, special washer and
disassembly, except for the visual check of the plunger.
clamp.
However, an injector that fails to pass one or more of the
6. Loosen the inner and outer adjusting screws (certain
tests is unsatisfactory. Perform all of the tests before
engines have only one adjusting screw and lock nut) on
disassembling an injector to correct any one condition.
the injector rack control lever and slide the lever away
from the injector.
Identify each injector and record the pressure drop and
fuel output as indicated by the following tests:
7. Lift the injector from its seat in the cylinder head.
Injector Control Rack and Plunger Movement Test
8. Cover the injector hole in the cylinder head to keep
foreign material out.
Place the injector in the injector fixture and rack freeness
tester J 22396. Refer to Fig. 8 and place the handle on
9. Clean the exterior of the injector with clean fuel oil
top of the injector follower.
and dry it with compressed air.
If necessary, adjust the contact screw in the handle to
ensure the contact screw is at the center of the follower
when the follower spring is compressed.
With the injector control rack held in the no-fuel position,
push the handle down and depress the
Fig. 12 - Injector Installed in Tester J 23010 with
Fig. 13 - Injector in Position for Testing with Tester J
clamping Head
23010
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