2-129
TM 9-2815-237-34
2-33. PRE-1990 (6.2L) FUEL INJECTION PUMP (DB2829-4523) CALIBRATION (Contd)
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Set the throttle lever in correct low idle position prior to calibration using throttle lever gauge. The
low idle screw must beat 34 ± 2 degrees as measured between vertical centerline of throttle shaft
bushing bore and throttle connection stud.
Flush the pump with calibrating oil to remove metal chips and possible contamination.
Before mounting the pump on the test stand, check the drive shaft for freedom of rotation in the
housing. Pump should be mounted securely in the appropriate adapter, and the intermediate
coupling checked for freedom of movement.
Connect supply and return lines securely.
Install high pressure injection lines. Use copper gaskets or steel washers where required. Leave fuel
line connections at the pump and nozzles loose.
Apply 17.6 V to electric shutoff solenoid and operate pump at 2000 rpm (WOT) for 10 minutes to
bring to operating temperature and clear air from system.
Tighten all connections securely. Check connections for leaks while operating.
Set transfer pump pressure at 2000 rpm (WOT) for 70-76 psi (482.7-524 kPa); test stand boost
should be set at 5 ± 0.5 psi (34.5 ± 3.4 kPa).
Set return oil flow to 225-375 cc/minute at 2000 rpm (WOT).
Measure housing pressure:
(a) Check housing pressure at 650 rpm, with throttle shaft in low idle position, pressure should
be 8-12 psi (55-83 kPa).
(b) Energize housing pressure cold advance solenoid with 17.6 V, housing pressure should be
0-1 psi (0-6.9 kPa).
With governor cover removed and throttle shaft in low idle position, set min-max governor assembly
for 14.0 ± 2 mm3/stroke at 650 rpm (fuel reading with cover installed).
Check electric shutoff solenoid for pull-in with 17.6 V maximum with throttle lever in low idle
position at 400 rpm.
Transfer pump lift should be 18 in. Hg (60.8 kPa) at 400 rpm.
Mechanical/Light Load Advance Setting
(a) Check housing pressure at 650 rpm, with throttle shaft in low idle position, pressure should
be 8-12 psi (55-83 kPa).
(b) With throttle in a WOT position, rotate face cam to its maximum lift position in contact with
the cam roller.
(c) At 2000 rpm, adjust trimmer screw for 1.5 degrees cam advance.
(d) Set throttle for 22.5 ± 1 mm3/stroke at 1500 rpm and rotate face cam to obtain 3.5 degrees
cam advance.
(e) Tighten face cam screw to 28-32 lb-in. (3-4 Nm) and check face cam retention.
(1) Put 0.005-in. (0.127 mm) feeler gauge between throttle shaft mylar washer and housing
(2) Put throttle shaft in idle position. Squeeze throttle shaft and face cam tightly toward each
other and rotate face cam as lower roller rests approximately in middle at low idle step.
Tighten screw to 30 lb-in. (3 Nm) with torx drive and remove feeler gauge.
Set total throttle travel, With throttle in low idle position, align zero degree mark on protractor
with center of rib on rocker lever. Move throttle to WOT and adjust maximum travel screw to
80-84 degrees.
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