MAINTENANCE OF THE M88A1 - OD1672 - LESSON 3/TASK 1
to be conducted by completing the other steps of the ENGINE HARD TO START
procedure, listed in item 71 of Table 2-3 in TM 9-2350-2556-20.
Maintenance and Repair. Water should be drained from both the primary
and secondary fuel filters on a weekly basis. The primary filter should be
replaced semiannually and the secondary filter annually.
troubleshooting procedure revealed that the APU fuel filters were dirty and
clogging up to the point that the flow of fuel to the engine was being
restricted making it hard for the engine to start.
The fuel filters,
therefore, must be replaced. The following steps describe the procedure for
the removal and installation of the fuel filters, and the bleeding of the
APU fuel system after installation of the fuel filters.
(1) Removal of Fuel Filters.
Step 1. Open the grille doors (3) and (4) (refer back to figure 9 on page
28) on the engine deck, which provides access to the APU engine fuel filters
(figure 32, view A, on the previous page).
Step 2. Remove the two screws and lockwashers on top of both the primary
and secondary fuel filters.
Step 3. If not opened, open the drain cocks on the bottom of each filter to
let the excess fuel drain out before removing them.
Place an empty
container to catch the excess fuel under the fuel filters before opening the
Step 4. With the use of an oil filter wrench, provided in the using unit's
maintenance shop set, remove the dirty and clogged up oil filters.
(2) Installation of Fuel Filters.
Step 1. Remove the protective plugs from the bottom of the new fuel filters
in preparation for installing the drain cocks from the old fuel filters.
Step 2. Remove the drain cocks (figure 32, view B) from the bottom of the
old fuel filters and install then on the bottom of the new fuel filters.
Make sure the drain cocks are shut tight to prevent leakage of fuel while
the engine is in operation.