Section II. AIR COOLING SYSTEMS

TM 5-3835-222-BD

(2) Start Engine

Damage Found To:

-Head Gasket . . . . . . . . . . . . . . . . . . . . Go To Para 3-6.

-Internal Engine Water Jacket . . . Go To Para 3-5.

- T h e r m o s t a t . . . . . . . . . . . . . . . . . . . . . . Go To Section III.

-Coolant Flow/Water Pump . . . . . . Go To Section Ill.

-Cooling Fan . . . . . . . . . . . . . . . . . . . . . Go To Specific TM.

-Air Flow Through Radiator . . . . . . Go To Section II.

-Fuel Filters . . . . . . . . . . . . . . . . . . . . . . Go To Section II.

NOTE:

Procedures boxed in this index can be used for training purposes.

6-3. Repair Procedure Index.

Paragraph

Shrouds, Air Cooling Damaged . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-5

Thermostat Stuck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-7

Engine Coolant Frozen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-6

Radiator Leaking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-9

Hose Clamp Broken . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-10

Hose Leakage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-11

Hose Collapse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-12

Hose Improvisation (Low Pressure) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-13

Section II. AIR COOLING SYSTEMS

6-4. General. Cooling system failures can result in engine failure and therefore must be dealt with

if the engine is expected to operate for any length of time. Cooling system problems most often

are indicated on the operator's instrument panel. While temporary overheating indications may result

from excessive workload on the engine, repeated or constant indication of overheating is almost

always followed by a major cooling problem.

6-5. Shrouds, Air Cooling Damaged. Shrouds are used to direct the cooling air over the hot engine.

Bent or torn shrouds will upset the flow of air and cause hotspots to occur which can cause internal

engine failures. Torn shrouds can be bent back into shape and patched with sheet metal, epoxy

kits or tape to restore the proper air flow. At minimum, they must be bent to prevent contact with

moving compartments. If the existing shrouds cannot be repaired, new shrouds must be fabricated

from sheet metal.

Section Ill LIQUID COOLING SYSTEM

6 - 6 General. During performance of repairs, or as a result of leakage, the coolant may become lost.

A liquid cooled engine cannot operate for long without coolant. When normal coolants are not available,

a substitute may be used. Any liquid, except gasoline or jet fuels, can be used as a substitute,

but some liquids will deteriorate the cooling system rubber components. Petroleum products will not

transfer the heat as efficiently as a water-based coolant, but will work if nothing else is available.

Old engine oil or fluids drained from damaged vehicles, transmission oil, or hydraulic systems may be

a possible source of fluids. The cooling system must be drained and flushed as soon as possible if

petroleum-based fluids are used.

6-2