TM-9-2815-220-24

AVDS-1790 2CA, 2DA and 2DR Air-Cooled 12-Cylinder Diesel Engines

TECHNICAL MANUAL; UNIT, DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE MANUAL FOR AVDS-1790 2CA, 2DA and 2DR Air-Cooled 12-Cylinder Diesel Engines

TM-9-2815-220-24 - Page 147 of 1563

TM 9-2815-220-24

FUEL SYSTEM ABNORMAL CONDITIONS

0020 00

MALFUNCTION 6:

Fuel injection pump deficiencies.

PROBABLE CAUSE

CORRECTIVE ACTION

(1) Adjust low-idle stop screw on fuel injection

pump.

NOTE

Required only when engine speed

cannot be adjusted as described in WP

0040, Engine Operating Parameters.

a. Fuel injection pump governor low-idle

speed adjustment improper.

(2) If low idle speed cannot be obtained,

replace fuel injection pump (WP 0115, Fuel

Injection Pump Assembly Replacement).

b. Fuel injection pump governor high-idle

speed improper.

(1) Check high-idle speed as follows:

PROCEDURE

OBSERVATION

ANALYSIS

High Idle Test

NOTE

Use a calibrated tachometer

for this test.

Start engine and warm-up to

normal operating temperature

(140

°

F).

Engine speed

2500-2640 rpm.

Speed is normal and governor

no-load adjustment is proper.

Engine speed below

2500 rpm.

Speed too low.

With transmission in "neutral",

depress accelerator pedal fully for

approximately 10 seconds.

Engine speed exceeds

2640 rpm.

Speed too high.

PROBABLE CAUSE

CORRECTIVE ACTION

(2) Check linkages and adjustment (WP 0043)

then repeat High Idle Test (above).

b. (Continued)

Fuel injection pump governor

high-idle speed improper.

(3) Replace fuel injection pump (WP 0115,

Fuel Injection Pump Assembly

Replacement).

c. Fuel-metering governor mechanism

binding, loose, worn or broken.

(1) Replace fuel injection pump (WP 0115,

Fuel Injection Pump Assembly

Replacement).

WP 0020 00-5