Calibration of Code B and F Pumps

TM 9-2910-226-34

flow, Flow should be 5 cc or less to meet

pumps). Fuel pressure should be 30-40 psi. With

specification. If fuel flow is not to limit, the pump

operating lever in idle position, adjust low-idle speed

must be shut down and the high-speed (inner)

screw to obtain fuel flow per Table 3-5 or 3-4. If

governor spring and spacer(s) must be checked and

reading is not within limit, loosen idle adjustment

adjusted. (See step c. (4) above for procedure).

screw locknut and turn idle adjustment screw (fig. 3-

Check condition of fuel control unit and pin (para 3-

173). Turn screw clockwise to increase fuel delivery

44).

and counterclockwise to decrease fuel delivery.

(5) Adjust speed to 1200 rpm and check fuel

Adjust screw to obtain specified flow, and tighten

pressure on gage (A, fig. 3-162) at compensator

screw locknut.

inlet. Fuel pressure should be 40-55 psi. Adjust

(8) Check 2600 rpm full-load fuel flow. If fuel.

droop screw to obtain fuel flow per Table 3-6. (See

flow does not fall within limits repeat steps (2)

step c. (5) and c. (6) above for procedure.)

through (7) above.

(6) If fuel flow cannot be adjusted to these

(9) Reduce test stand rpm to a minimum. When

speed reaches minimum push drive motor stop

limits, check engagement of compensator stop plate

button (DD, fig. 3-162) and turn speed shifting

and linkage and angular position of smoke limit

crank (S) to LOW RANGE.

torque cam. (See steps c (5) and (6) above for

procedure.)

(10) Restart the test stand and adjust speed to

150 rpm with operating lever in full-load position, set

(7) Reduce speed to 700 rpm and check fuel

pressure on gage (A, fig. 3-162) at compensator

count at 1000 and collect fuel in fuel burettes. Check

inlet. Fuel pressure should be 30-40 psi. With

fuel pressure gage (A). Reading should be 7 psi

operating lever in idle position, adjust low idle

minimum. Fuel flow should be in accordance with

adjustment screw (fig. 3-173) to obtain fuel flow per

Table 3-5 or 3-4. If fuel pressure is below 7 psi, in-

Table 3-6. (See step c(7) above for procedure. )

spect fuel supply pump (para 3-20). If fuel flow is

below the specified minimum, the hydraulic head

(8) Check 2600 rpm full-load fuel flow. If fuel

flow does not fall within limits, repeat (2) through (7)

and plunger are excessively worn and the head must

above.

be replaced. Replace hydraulic head assembly if

proper flow is not obtained, and retest the pump.

(9) Reduce test stand rpm to a minimum. When

speed reaches minimum, push drive motor stop

(11 ) Pull injection pump fuel shutoff rod. Fuel

button (DD, fig. 3-162) and turn speed shifing crank

should stop flowing immediately each time the rod is

pulled. If fuel does not stop, check fuel shutoff to

(S) to LOW RANGE.

make certain the rod is properly engaged with the

(10) Restart the test stand and adjust speed to

150 rpm with operating lever in full-load position.

control unit lever.

Set count at 1000 and collect fuel in fuel burettes.

(12) On code G pumps, set droop screw per

Fuel flow should be in accordance with Table 3-6. If

special instructions in Table 3-5. On code E pumps,

the fuel flow is below specified limit, the hydraulic

set droop screw per special instructions in Table 3-4.

head and plunger are excessively worn and the head

d. Calibration of Code B and F Pumps. Calibrate

must be replaced. Replace hydraulic head assembly

injection pump code B or F using Table 3-6.

if proper flow is not obtained, and retest the pump.

(1) Use two-hole injector nozzle and holder

(11) Pull injection pump fuel shut-off rod. Fuel

assemblies (fig. 3-163, 3-169 and 3-170) with code F

should stop flowing immediately each time the rod is

pump, and one-hole injector nozzle and holder

pulled. If fuel does not stop, check fuel shut-off to

assemblies with code B injection pump.

make certain the rod is properly engaged with the

NOTE

control unit lever.

Code B pumps used to replace code F pumps

e. Calibration of Code A Pump. Calibrate code A

must be calibrated with two hole nozzles.

injection pump using Table 3-7.

After calibration, tag the pump making one

(1) Use one-hole nozzle and holder assemblies.

of the following statements as applicable:

(2) Adjust speed to 3100 rpm and check fuel

FOR USE ON CODE B ENGINE

pressure on gage (A, fig. 3-162) at compensator

ASSEMBLY (LDS-465-lA)

inlet. Fuel pressure should be 60-80 psi. Fuel flow

FOR USE ON CODE F ENGINE ASSEM-

should be in accordance with Table 3-7, depending

BLY (LDS-465-1)

on fuel used, Fuel flow adjustment is made by ad-

(2) Adjust speed to 2850 rpm and check fuel

justing high-speed adjustment screw (fig. 3-173).

pressure on gage (A, fig. 3-162) at compensator

(Refer to step c (2) above for procedure. )

inlet. Fuel pressure should be 60-80 psi. Fuel flow

(3) Adjust speed to 2800 rpm and check fuel

should be in accordance with Table 3-6, depending

pressure on gage (A, fig. 3-162) at compensator

on fuel used. Fuel flow adjustment is made by ad-

inlet. Fuel pressure should be 60-80 psi. Adjust stop

justing high-speed adjustment screw (fig. 3-173).

plate guide screw (fig. 3-174) to obtain fuel flow per

(See step c. (2) above for procedure.)

Table 3-7. (Refer to c (3) above for procedure. )

(3) Adjust speed to 2600 rpm and check fuel

(4) Adjust speed to 3150 rpm and check fuel

pressure on gage (A, fig. 3-162) at compensator

flow. Flow should be 5 cc or less to meet

inlet. Fuel pressure should be 60-80 psi. Adjust stop

specification. If fuel flow is not within limit, the

plate guide screw (fig. 3-174) to obtain fuel flow per

pump must be shut down and the high-speed (inner)

table 3-6. (See step c. (3) above for procedure, )

governor spring must be checked and adjusted. (See

(4) Adjust speed to 2940 rpm and check fuel

3-107