TRUCK SERVICE MANUAL
FUEL SYSTEM
15. All counter wheels must be set at zero (0) as a
starting point. Fig. 6188.
16. Shift the silver-colored counter wheels to the
right, rotate as necessary then release them to
indicate 1020 strokes. Rotate empty vial into
position by turning vial knob.
17. Clear the counter by rotating with thumb screw
for one complete revolution. All white counter
wheels must show zero (0). Fig. 6189.
18. Engage the counter and divert fuel to the
vial for measurement by pressing and releasing
the red flow start switch.
19. Stir the fuel with a rod to settle out the foam,
Fig. 6-1-88, F60138. Start counter at zero
then, check the amount collected in the vial at
the end of the 1020 countstrokes.
20. Look directly into the vial at fuel level to avoid
parallax. If this reading shows 129 cc which is 3
cc below the correct injector master delivery
specifications (132 cc @ 120 psi), or another
value, repeat test. Fig. 6190.
21. Dump the fuel from the vial and repeat the test at
least twice to insure consistent results.
22. If 3 cc low, it will be necessary to set the counter
up to approximately 1043 strokes or about 7 to 8
strokes for each cc. Roll the counter back, all
white counter wheels must show zero (0).
Note: If the counter is set beyond 1050 strokes, it is a
good indication test stand is not properly installed or
calibrated.
Fig. 6-1-89, F60139. Clear counter
23. Repeat the tests and adjust the counter as
necessary, to obtain 132 cc delivery at 120 psi
[827 kPa] with fuel temperature at 90 deg. to 95
deg. F [32 to 35 deg. C], while the master
injector is in the test stand. Check readings for
three cycles to insure repeatability. After each
four cycles, reclamp injector to insure maximum
accuracy. At this point the test stand is correctly
calibrated.
Note: In reading the level of fuel in vial, be certain to
read it at the fuel level. Fig. 6190. When reading at "C"
height, you are too high. The reading at "B" is the
correct height. You are not looking up or down at the
fuel level, thereby avoiding parallax. Read the correct cc
at the point where fuel appears to change color.
Fig. 6-1-90, F60210. Read vial fuel level
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