TM 5-3805-280-24-2
Fuel System
INSTALL STANADYNE MODEL DB2 AND DB4 INJECTION PUMP
35
38
A--Front Plate Timing
C--Pump Drive Gear
Mark
Retaining Nut
B--Pump Timing Mark
Pump drive shaft index pin may be
Injection pump mounting flange timing mark (B) and
damaged if pin is not properly
front plate timing mark (A) presence and alignment
aligned with drive gear key slot and
MUST BE verified before removing pumps from
nuts are tightened more than three
engine. When pump is reinstalled on engine, time
turns.
pump by aligning these two (external) marks. DO NOT
reference internal timing marks (on pump cam ring and
4. Install three flat washers, lock washers, and hex
governor weight retainer) for accurate pump timing.
nuts onto pump mounting studs. Tighten nuts three
turns only so that pump will not fall off mounting
1. Lubricate a new square sealing ring with clean
studs.
engine oil, install ring into groove on front face of
pump mounting flange. Slide injection pump onto
NOTE: The pump drive gear should begin to move
mounting studs while inserting pump shaft into drive
forward (away from engine front plate) with the
gear.
pump when flange is approximately 3.2 mm
(1/8 in.) away from engine front plate.
IMPORTANT: Shaft roll pin may be easily damaged
if improperly assembled. Pump drive
gear should not move when initially
5. Install pump mounting flange flush to engine front
installing pump index pin into drive
plate with drive gear held flush against front side of
gear key slot.
engine front plate.
2. Check pump shaft and index pin for proper
IMPORTANT: DO NOT use tightening force of
alignment with pump drive gear key slot.
pump mounting stud nuts to pull
pump shaft into drive gear I.D.
3. Install injection pump partially onto mounting studs
without engaging pump pilot hub into engine front
6. With the pump shaft index pin properly engaged in
plate.
the drive gear key slot, finger tighten mounting stud
nuts.
IMPORTANT: DO NOT tighten hex nuts more than
three full turns on mounting studs.
Continued on next page
RG,35,JW7606
1920NOV971/4
13-417
