DETROIT DIESEL 53
rust preventive compound should be removed before
installing the parts in an engine.
If parts are not to be used immediately after cleaning,
dip them in a suitable rust preventive compound. The
Many service replacement parts are available in various
The purpose of parts inspection is to determine which
undersize and/or oversize as well as standard sizes.
parts can be used and which must be replaced.
Also, service kits for reconditioning certain parts and
Although the engine overhaul specifications given
service sets which include all of the parts necessary to
throughout the text will aid in determining which parts
complete a particular repair job are available.
should be replaced, considerable judgment must be
exercised by the inspector.
A complete discussion of the proper methods of
precision measuring and inspection are outside the
The guiding factors in determining the usability of worn
scope of this manual. However, every shop should be
parts. which are otherwise in good condition, is the
equipped with standard gages, such as dial bore gages,
clearance between the mating parts and the rate of wear
on each of the parts. If it is determined that the rate of
wear will maintain the clearances within the specified
In addition to measuring the used parts after cleaning,
maximum allowable until the next overhaul period, the
the parts should be carefully inspected for cracks,
reinstallation of used parts may be justified. Rate of
scoring, chipping and other defects.
wear of a part is determined by dividing the amount the
part has worn by the hours it has operated.
possible, be located away from the disassembly and
Following cleaning and inspection, the engine should he
cleaning operation. Also, any machining operations
assembled using new parts as determined by the
should be removed as far as possible from the
Use of the proper equipment and tools makes the job
Particular attention should be paid to storing of parts
progress faster and produces better results. Likewise, a
and sub-assemblies, after removal and cleaning and
suitable working space with proper lighting must be
prior to assembly, in such a place or manner as to keep
provided. The time and money invested in providing the
them clean. If there is any doubt as to the cleanliness of
proper tools, equipment and space will be repaid many
such parts, they should be recleaned.
When assembling an engine or any part thereof, refer to
Keep the working space, the equipment, tools and
the table of torque specifications at the end of each
engine assemblies and parts clean at all times. The
section for proper bolt, nut and stud torques.
area where assembly operations take place should, if
A serviceman can be severely injured if caught in the
position. This will mean the governor is in the no-fuel
pulleys, belts or fan of an engine that is accidentally
position. The possibility of the engine firing by
started. To avoid such a misfortune, take these
accidentally turning the fan or, in-the case of vehicle
precautions before starting to work on an engine:
application, by being bumped by another vehicle is
Disconnect the battery from the starting system by
removing one or both of the battery cables. With the
Some Safety Precautions
electrical circuit disrupted, accidental contact with the
Working On The Engine
starter button will not produce an engine start.
1. Consider the hazards of the job and wear protective
Make sure the mechanism provided at the governor
gear such as safety glasses, safety shoes, hard hat, etc.
for stopping the engine is in the stop
to provide adequate protection.
1972 General Motors Corp.