to replacing the faulty component, you must realign the
5. Perform failure analysis.
equipment and make certain the foundation bolts are
In the following paragraphs, we will briefly describe
torqued to the proper values.
each of these operations. Again, try to envision your
Following the five troubleshooting operations in
responsibilities as a GSM in each of these steps.
their logical sequence will help you to be more efficient
Identifying the Symptom. After recognizing an
and effective in your troubleshooting responsibilities.
equipment malfunction, a good technician will then use
Remember, your most important tool in troubleshooting
all available aids designed into the equipment to
is your thorough knowledge of the equipment or system
elaborate on the symptom. As a GSM, you have several
in terms of its normal operational characteristics. The
available aids. By using the front panel controls,
next most important tool is to follow the correct
indicators, and other testing aids, you can obtain a better
troubleshooting procedures or operations in their proper
description of the symptom. Once you identify the
sequence.
symptom, your next step is to identify the malfunction.
TESTS AND INSPECTIONS
Identifying the Malfunction. In this step in the
troubleshooting process, you must determine some
The operational performance of the FO system on
logical choices for the basic cause of the symptom. Your
board your ship should be constantly monitored. Good
determinations will be based on your knowledge of
maintenance habits and the proper use of the PMS as a
equipment or system operation and a full description of
scheduling tool for routine tests and inspections will
the symptom. The overall functional description of the
ensure the optimum performance from your ship's FO
equipment or system in the appropriate technical
system. In the following paragraphs, we will describe
manuals can help you outline some logical choices.
some components of the FO system and the most
Localizing the Malfunction. Now that you have
common tests and inspections. As you advance in the
identified the malfunction, you must localize its basic
GSM rating, you will be required either to perform these
source. Localizing the malfunction is normally
inspections and tests or to make certain they have been
accomplished by using the troubleshooting flow charts
done.
and block diagrams in the technical manuals. If one test
does not prove that the function is faulty, test the next
Fuel Pump Coupling
logical choice. Continue this procedure until you can
localize the faulty function.
Inspection of the fuel pump coupling similar to the
one shown in figure 5-1 is usually performed
Locating the Cause of the Malfunction. After
semiannually. The normal steps of this inspection are
localizing the malfunction, you must make additional
disassembling the coupling cover, cleaning out the old
choices to find which component or circuit is at fault. If
grease, and inspecting the coupling grid and hub teeth.
the trouble is not immediately apparent, use the proper
If your inspection shows that the fuel pump coupling is
test methods to further isolate the fault. Continue this
satisfactory for operation, then your next steps are to
process until you locate the specific cause. Defective
reinstall the grid, apply the specified grease, and
components, vibration, misalignment, improper wiring,
reassemble the coupling cover.
and improperly soldered components are all examples
that might be specific causes of an engine problem.
In inspecting the fuel pump coupling, there are some
key points you should look for during the disassembly
Performing Failure Analysis. After you have
and inspection steps. We will describe these points in the
located the fault, review your troubleshooting
following sections. Remember, you should consider
procedures before you make the repair. This step will
both the symptoms of the malfunctions and the signs of
help you determine exactly why the fault had a certain
normal operation when you are checking the
effect on the equipment. It will also help you make
components.
certain that the fault you found is actually the cause of
the malfunction and not the result of the malfunction.
COVER SEAL. A symptom of deterioration of the
For example, excessive vibration may have caused a
coupling cover seal or a bad seal is the collection of
component failure. Upon analysis, you may have
grease on the inside of the coupling guard or on the pump
determined that equipment misalignment caused the
base, depending on the type of pump installation. You
vibration, which, in turn, caused the component to fail.
can perform a check of the cover seal at any time, even
The real culprit could simply be loose equipment
with the pump in operation. If a seal is bad, the natural
foundation bolts that allowed the vibration. In addition
thing for you to do is to replace it. Before you replace
