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 165 of 1563

TM 9-2815-220-24

INTAKE MANIFOLD HEATER ABNORMAL OPERATION

0023 00

MALFUNCTION 1:

(Continued)

Manifold heater inoperative.

Ignition Unit Operation

NOTE

Disconnect purge pump fuel hose

quick-disconnect coupling at engine

before performing test.

WARNING

High Voltage!

(See decal on unit.)

Voltage High Amperage Output.

PROCEDURE

OBSERVATION

ANALYSIS

High-tension spark indicates

ignition unit operation

normal.

Remove high-tension wire

from igniter (spark plug).

Position lead wire end to

ground for spark gap

(1/4 inch)

Note high-tension spark (hot

bluish-white) across gap (lead-

to-ground).

Improper spark or no spark

indicates ignition unit or

ignition unit lead is defective.

Replace unit and lead

(WP 0088 Manifold Heater

Assembly and Related Parts

Replacement).

Spark Plug Operation

WARNING

High Voltage!

High-tension spark indicates

spark plug firing, operation

normal.

Remove spark plug,

reconnect wire to spark

plug, ground plug body to

engine and press manifold

heater switch "ON".

Note high-tension spark across

spark plug electrodes.

No spark, the spark plug is

defective.

Replace spark

plug.

Solenoid Valve(s) Operation

Evidence of action indicates

normal solenoid valve

operation.

Press manifold heater

switch intermittently "ON"

and "OFF".

Note audible "click" or opening

and closing valve action (by

touch) of both solenoid valves

(fuel supply and fuel return).

No audible "click" or action

indicates solenoid valve(s) is

defective.

WP 0023 00-3