Injector Spray Pattern Check.

*TM 9-2815-213-34

(1) Install factory calibrated master injec-

draulic reservoir as originally established with load test cell.

tor gage (36, fig. B-28), in test stand to adjusting

Close hydraulic valve (fig. 3-61) to lock injector in clamped

other injectors for fuel delivery.

position. Connect inlet and drain connectors (fig. 3-64) to

injector.

CAUTION

(13) Start test stand motor and allow to run until fuel

The master injector must never be tam-

temperature reaches a minimum of 80 degrees.

pered with.

(14) Adjust fuel pressure by turning pressure

(2) Fill hydraulic fluid reservoir.

regulator knob until fuel pressure gage

(3) Test oil tank on stand must be kept at

shows 120 psi. If this pressure can not be achieved, the

least ye full of diesel fuel.

trouble probably is due to a sticking air regulator, or to a worn

(4) Aline timing mark (fig. 3-60) and close

gear pump. Pres. sure of 120 psi must be maintained at all

hydraulic valve and open the air valve (fig. 3-61).

times during calibration and testing.

Place load cell tester (1, fig. B-29) in test stand

(15) All counter wheels (fig. 3-60) must be set at

and clamp in place by opening hydraulic valve

zero (0) as a starting point.

(fig. 3-61).

(a) Shift silver-colored counter wheels to right, rotate as

CAUTION

necessary then release them to indicate 1020 strokes.

Never operate test stand with load cell

Rotate empty vial into position by turning vial knob.

in position.

(b) Clear counter by rotating with thumb screw until all white

(5) Adjust air pressure by turning knurled

counter wheels show zero.

(16) Engage counter and

button on air regulator until the load cell indi

divert fuel to vial for measurement by pressing and releasing

cates within marked band on load cell gage (0

red flow start switch.

3-62). Lock knurled button in place with lock-

(17) Stir fuel with a rod to settle out foam. Check

nut. Note air gage pressure (gage at top

amount collected in vial at end of 1020 counter strokes.

hydraulic reservoir).

(18) Look directly into vial at fuel level to avoid

(6) Remove load test gage by opening ]

parallax. If this reading shows 129 cc which is 3 cc below

draulic valve and returning air valve knob center

correct injector master de livery specifications (132 cc @ 120

position. With cylinder rod in down posi- tion, check

psi.), or an- other value, repeat test.

to make sure hydraulic fluid shows hydraulic oil lever

(19) Dump fuel from vial and repeat test at least

sight bulb.

twice to insure consistent results.

(7) Open air valve. While cylinder rod is at

(20) If 3 cc low, it will be necessary to set counter up

the top of its travel, check to make sure there no air

to approximately 1043 strokes or

in hydraulic fluid sight glass.

about 71/2 strokes for each cc. Roll counter back,

(8) Make sure injector seat contains 0.0

all white counter wheels must show zero (0).

(21) Repeat

inch restrictor orifice when calibrating test stand.

tests and adjust counter as necessary to obtain 132 cc

(9) Place injector adapter (fig. 3-63) o~

delivery at 120 psi. with fuel temperature at 80 degrees to

master injector and engage locators in inject

100 degrees Fahrenheit while master injector is in test stand.

mounting holes. Make sure seat is retracted a timing

Check readings for three cycles to insure repeatability, at this

marks are alined at timing wheel.

point test stand is correctly

(10) Position test stand link (marked NV NH,

calibrated.

H) over injector plunger link and place adapter and

(22) Remove master injector from test

injector assembly in injector se tip back until link is

stand.

below machine push rod. necessary adjust bracket

c. Injector Spray Pattern Check.

so link is alined but r rubbing.

(1) Locate injector spray angle tester (6, fig. B-29)

NOTE

on or near injector test stand (fig. 3- 59) or other source of

Turn injector plunger so that class size

50 p.s.i. constant fuel pressure, so that injector inlet

marking on top of spring retainer is midway

connection of test stand will reach injector to be checked.

between inlet and drain connec- tions.

Use injector test oil or diesel fuel to perform test.

(11) Open air valve (fig. 3-61) and as

jector goes in clamped position make sure plunk

link is properly alined and engaged in link gui

(12) Check air gage pressure at top of ]

3-28