Chapter 3. REPAIR OF RADIATOR

CHAPTER 3

REPAIR OF RADIATOR

Section I. RADIATOR CONSTRUCTION

3-1. GENERAL

a. The radiator of a motor vehicle is an essential

element of the cooling system. It must function correctly if

the engine is to escape serious damage from overheating.

An engine is cooled by circulating water which passes

through the cylinder block. It draws out the heat and then

releases it to the air while flowing through the radiator. If

this circulation is hindered or coolant leaks from the

radiator, immediate repairs must be made to protect the

engine.

b. Automobile, truck, and tractor radiators consist of

two water tanks (upper and lower) joined by a core which

does the actual cooling (fig 3-1). Water from the cylinder

block usually enters the upper tank through the inlet, flows

through the core, and leaves by lower tank. A 3/8-inch

overflow pipe in upper tank (figs 3-1, 3-2 and 3-3) carries

Figure 3-2. Stamped metal radiator.

away excess steam or water. In the radiator assembly

shown in figure 3-1, cast-metal tanks are bolted to the side

members. Gaskets between the tanks and core make a

watertight connection. Figure 3-2 illustrates a stamped

metal radiator formed by soldering drawn or stamped

metal tanks to the radiator core. The side members are

straps of sheet steel soldered to the upper and lower

tanks. This much lighter construction has generally

replaced the cast metal type. In passenger cars and light-

duty trucks, where it is usually concealed by the hood and

radiator grille.

Figure 3-3. Stamped metal radiator tank (cutaway).

3-2.

Water Tank

Almost all radiator tanks are cast or stamped in one piece

to reduce the number of potential leaks. A baffle plate in

the upper tank, below the filler neck,

Figure 3-1. Cast metal radiator.

3-1