A fuel inlet stud can be fabricated with a 1/4
.18 NPT pipe die. High pressure tubing must be
used between the Nozzle Test Stand and the
Always check to make sure that all external
connections are tight and that the Nozzle Test
Stand is in good order.
(8) Slowly operate the Nozzle Test Stand until a
pressure of 400 psi is achieved. A rapid drop in pressure in-
dicates that a leak is present. The pressure must remain
above 250 psi for at least 30 seconds.
DO NOT EXCEED A PRESSURE OF 400 PSI.
(9) Visual inspection should be as follows:
(a) Check for leakage by the head locating screw
(13, figure 7-34).
(b) Slight leakage by control unit shaft
is normal and is necssary to lubricate
Fuel leakage between the control unit body (4)
and pump housing (6) indicates that either the
o-ring (33) is damaged or the mating surfaces are
the o-ring (33) and retest the
If fuel leakage is eXCeSSive (Class III,
see TM 5-6115-585-12,
Maintenance Checks and Services (PMCS) at control
shaft or continues past o-ring (33) replace
(c) Check for leakage of fuel around the face gear
(28). If leakage is evident, disassemble pump and inspect
O ring (19).
(d) Check for fuel leakage between top of housing
and head flange. To correct, disassemble and replace upper
hydraulic head O ring (18).
f. Install (Method 1).
(1) Turn engine flywheel to the port closing mark
(PC) on the front cylinder (closest to blower wheel) com-
pression stroke (see figure 7-44).
(2) Remove timing hole screw located on pump
mounting flange (figure 7-42). Insert a 1/8 inch diameter
wire into the hole.
(3) Rotate pump face gear until wire slips into place
locking the gear in position.
(4) Mount pump on crankcase (see figure 7-32) (be
sure shims (5) are in place) and secure in position using four
hexagon, nuts (2), flatwashers (4) and lockwashers (3). If
O ring seal between pump and crankcase is worn, cracked
or otherwise defective, replace it.
(5) Remove wire. Install timing hole screw and
Figure 7-42. Injection Pump Installation
g. Install (Alternate Method 2).
(1) If pump was not timed by method 1, time now
using alternate method 2 below.
(2) Connect flexible fuel inlet line to pump inlet.
Connect fuel return line.
(3) Connect each fuel outlet line to the proper pump
outlet (see paragraph 7-2).
(4) Connect governor linkage to governor arm.
(5) Start and run engine. Adjust governor linkage if
required (see paragraph 7-3).
A maximum throttle stop screw, located on the
injection pump control assembly, limits the
maximum amount of fuel which can be injected
into the engine. This screw should not be tam-
pered with; it has been properly adjusted at the
factory to protect the engine from over-fueling
(see figure 7-22).
h. Adjust/Time on Equipment.
(1) Time the injection pump to the engine by using
the proper thickness timing button between pump plunger
and tappet (ace figure 7-3 3). Use method 1 when replacing
an old pump if the port closing dimensions and bottom
number of the old pump were recorded. Use method 2 if
the dimensions are lost, and old pump is being timed, or
when replacing either the camshaft or crankshaft: