5.3
Section 5
Fuel System and Governor
5
Replacing the Fuel Pump
Nonmetallic fuel pumps are not serviceable and must
be replaced when faulty. Replacement pumps are
available in kits that include the pump, fittings, and
mounting gasket.
1. Disconnect the fuel lines from the inlet and outlet
fittings.
2. Remove the hex flange screws, fuel pump, and
gasket.
3. If necessary, remove the fittings from the pump
body.
4. Install Fittings
Threaded Fittings
a. Apply a small amount of Permatex
®
Aviation
Perm-a-Gasket (or equivalent) gasoline-
resistant thread sealant to the threads of
fittings. Turn the fittings into the pump
5 full
turns
; continue turning the fittings in the
same direction until the desired position is
reached.
Lock-in Fittings
The inlet and outlet hose fittings must be
installed into the fuel pump prior to mounting.
The pump housing incorporates a special locking
feature to retain the fittings. The release tabs
must
be depressed when the fittings are installed
or removed, to avoid damage to the fitting O-
Rings and a potential fuel leak.
Do not
attempt to
install or force the fittings into place without
first depressing the tabs. There is a snap ring
included with the new fuel pump kit that will
serve as a tool for this purpose.
a. Note the direction arrows molded into the
pump housing and position the snap ring so
the ends depress the two square release tabs
at the inlet end. See Figure 5-3.
Figure 5-3.
b. Lubricate the O-Ring on each fitting with oil.
c. Insert the 90° fitting until the toothed flange is
just outside of the pump body. Rotate the
fitting to the desired orientation and then
apply pressure to seat/snap it into the
housing. The flange face will be flush with the
end of the housing.
d. Transfer the snap ring to the opposite end and
repeat the sequence to install the straight
fitting. Remove the snap ring.
5. Clean off any remaining gasket material from the
fuel pump mounting surface. Refer to the pump
installation instructions to determine if the extra
spacer and gasket are required to mount the new
pump. Install new gasket, fuel pump, and hex
flange screws.
NOTE:
Make sure the fuel pump lever is
positioned to the RIGHT of the camshaft
(when looking at fuel pump mounting
pad). Damage to the fuel pump, and
subsequent severe engine damage could
result if the lever is positioned to the left
of the camshaft.
Torque the hex flange screws as follows:
Into new holes–
9.0 N·m (80 in. lb.)
.
Into used holes–
4.2-5.1 N·m (37-45 in. lb.)
.
6. Connect the fuel lines to the inlet and outlet
fittings.
