Chapter 1. INTRODUCTION - TM-750-2540007

CHAPTER 1

INTRODUCTION

Section I. GENERAL

Deficiencies detected in the equipment or materials should

1-1.

Scope

be reported using the Equipment Improvement

Recommendation section of DA Form 2407.

For

This manual contains maintenance instructions for all

instructions on the use of this form, refer to TM 38-750

levels of maintenance on cooling systems for tactical

Submit the completed DA Form 2407 to Commanding

vehicle engines. Liquid-cooled engines are the primary

General, U. S Army Tank-Automotive Command, ATTN

subject of these instructions.

AMSTA-ME, Warren, MI 48090.

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Forms and Records

1-3.

Reporting

Equipment

Publication

a. Authorized Forms Maintenance forms and

Improvements

records that you are required to use are explained in TM

The reporting of errors, omissions, and recommendations

38-750.

b. Recording. At the completion of the cooling

for improving this publication by the individual user is

encouraged Reports should be submitted on DA Form

system processing, the condition of the cooling system

2028 (Recommended Changes to publications) and

and the degree of freeze protection shall be recorded on

forwarded direct to Commanding General U S Army Tank-

DA Form 2408-1, Equipment Daily or Monthly Log or DA

Automotive Command, ATTN AMSTA-MAP, Warren, MI

Form 2409.

48090 A reply will be furnished directly to you.

c. Field Report of Accidents. The reports necessary

to comply with the requirements of the Army safety

program are prescribed in detail in AR 385-750.

d. Equipment Improvement Recommendations.

Section II. COMPONENTS OF COOLING SYSTEM

1-4. General

These passages are designed so that the coolant is

distributed in the proper proportions for efficient cooling

Cooling systems are made up of many individual

Engine block castings have holes in the lower portion of

components These operate in close association with each

the block These holes provide openings to the water

other to enable the engine to produce its power efficiently

passages and are necessary for removing the filler and

Reduced performance or failure of any one of these

when the block is cast The holes are sealed by disks

components will require servicing or repairing to restore

which are known as core hole plugs. Plugs offer some

engine performance to normal requirements The following

protection against block cracking when coolant water

illustration (fig 1-1) establishes a nomenclature for these

freezes These plugs occasionally leak Small leaks can be

typical components and shows their approximate location

detected by anti-freeze residue and calcium deposits

in a typical automotive cooling system In the illustration,

around the plug. Leaky core plugs should always be

the engine block and cylinder heads contain coolant

replaced.

passages which comprise the water jacket.

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