The highest pressure reference number shown on gage
2 will be reached just before injection ends. Use the
following reference values to determine the relative
acceptability of the injector. Reference values for
Series 71 injectors, are from 127 minimum to 146
The reference value obtained when
pop testing the needle valve
injectors is to be used as a trouble
shooting and diagnosis aid. This
injectors without disassembly. Exact
valve opening pressure values can
only be determined by the Needle
Valve Tip Test using tester J 23010
and tip test adaptor J 23010-129 or
auxiliary tester J 22640.
Injector High Pressure Test
This test checks for leaks at the filter cap gaskets, body
plugs and nut seal ring.
1. Clamp the injector properly and purge the air from
2. Close the Thru Flow valve. but do not overtighten.
Fig. 14 Assembling Injector Valve Parts on Tip
Tester Adaptor J 23010-129
3. Position the injector rack in the full-fuel position.
4. Place pump lever I in the vertical position.
5. Move lever 3 to the forward detent position.
6. The injector follower should be depressed rapidly (40
to 80 strokes per minute) to simulate operation in the
engine. Observe the spray pattern to see that all spray
orifices are open and dispersing the test oil evenly. The
beginning and ending of injection should be sharp and
Fig. 15. Adaptor and Tube Assembly on Injector
the test oil should be finely atomized with no drops of
Tester J 23010
test oil forming on the end of the tip.