Lesson 3/Learning Event 2
LEARNING EVENT 2:
TROUBLESHOOT THE 50-GPM PUMP UNIT
When the 50-GPM Pump fails to perform as it should, troubleshooting will be required to identify
the malfunction, the probable cause, and the proper corrective action.
Troubleshooting the Pump
This section provides information to be used in diagnosing and correcting unsatisfactory
performance or failure of the pump. Each malfunction is listed in the following table (figure 22
on page 56). A list of probable causes and corrective actions follows the listed malfunction. The
procedures for performing corrective action are discussed in Lesson 1.
Troubleshooting the Engine
This section contains troubleshooting information for locating and correcting most of the
operating troubles which may develop in the military standard engine. Each malfunction for an
individual component, unit, or system is followed by a list of tests or inspections which will help
you to determine the probable causes and corrective actions to take. You should perform the
tests, inspections, and corrective actions in the order listed.
This subcourse cannot list all the malfunctions that may occur, nor all the tests or inspections and
corrective actions. If a malfunction is not listed or is not corrected by listed corrective actions,
notify your supervisor.
Before beginning troubleshooting procedures, be sure all applicable operating checks have been
performed. The following instructions list the engine malfunction and, following the listed
malfunction, a series of steps to follow to identify and correct the problem.
Engine Fails to Start. If the engine fails to start, perform the following steps in sequence.
Step 1. Check to see if there is fuel in the tank. If the fuel tank is empty, refill the tank. If the
engine still fails to start, go to step 2.
Step 2. Remove the air cleaner cup on models 1A08-1 and 1A08-2. On engine model 1A08-3,
check the service indicator first. If it shows in the red, remove the air cleaner element. If the
engine starts, the air cleaner needs servicing. If the engine still fails to start, go on to step 3.