Keeping an internal combustion engine (diesel
or gasoline) in good operating condition demands
a well-planned procedure of periodic inspection,
adjustments, maintenance, and repair. If inspec-
tions are made regularly, many malfunctions can
be detected and corrected before a serious casualty
results. A planned maintenance program will help
to prevent major casualties and the occurrence of
many operating troubles.
The Maintenance and Material Management
(3-M) System provides a logical and efficient
approach to many maintenance problems. It pro-
duces a large reservoir of information about
equipment disorder and indicates what corrective
steps must be taken to prevent them.
Another aspect that must be considered in
connection with maintenance problems is the
safety requirement aboard ship. On some ships,
the 3-M System includes safety requirement cards.
A safety requirement card provides guidelines and
periodicity for the inspection of selected areas not
covered in the regular maintenance schedule.
Complete information about the 3-M System
is contained in the Maintenance and Material
Management (3-M) Manual, OPNAVINST
There may be times when service requirements
will interfere with a planned maintenance pro-
gram. In such event, routine maintenance must
be performed as soon as possible after the
specified interval of time has elapsed. All
necessary corrective measures should be
accomplished as soon as possible. Repair jobs
should not be allowed to accumulate, otherwise
hurried and inadequate work will result.
Since the Navy uses many models of internal
combustion engines, it is impossible to specify a
detailed overhaul procedure that would be
adaptable to all models. However, there are
several general rules which apply to all engines.
1. Detailed repair procedures are listed in
manufacturers instruction manuals and in
maintenance pamphlets. Study the appropriate
manuals and pamphlets before attempting any
repair work. Pay particular attention to tolerance
limits, and adjustments.
2. Observe the highest degree of cleanliness
in handling engine parts during overhaul.
3. Before starting repair work, be sure that
all required tools and replacements for known
defective parts are available.
4. Keep detailed records of repairs. Such
records should include the measurements of parts,
hours in use, and the names of the new parts in-
stalled. Analyses of such records will indicate the
hours of operation that may be expected from the
various engine parts. This knowledge is helpful
as an aid in determining when a part should be
renewed in order to avoid a failure.
Since maintenance cards, the manufacturers
maintenance manuals, and the various types of
instructions discuss repair procedures in detail,
this chapter will be limited to general informa-
tion on engine inspections, adjustments, and
maintenance, as well as some of the troubles
encountered during overhaul, the causes of such
troubles, and the methods of repair to be used.
Inspections and maintenance are vital in order
to maintain engines (diesel and gasoline) in