Fuel Pump and Strainer

blow through the lines with compressed air to make

(1) Disconnect auxiliary fuel lines, if used,

sure they are clear.

and operate the fuel selector valve (17) to OFF.

(2) Disconnect and remove hose assembly (2)

(5) Inspect the hose for cracks, fraying, and

between valve and fuel strainer. Remove pipe

damaged threads; replace a damaged hose.

e l b o w (3) and bushing (4).

(6) Inspect the 3-way valve for difficult

o p e r a t i o n and for cracked or damaged threads;

(3) Remove the drain plug (1) from the

replace a damaged valve.

bottom of the fuel tank. Be sure you have large

enough container in which to drain the fuel.

(7) Inspect a l l o t h e r p a r t s f o r c r a c k s ,

(4) Remove the four cap screws (8), flat

distortion, a n d d a m a g e d t h r e a d s ; r e p l a c e a n y

washers (7), lock washers (6), and nuts (5) that

damaged parts.

s e c u r e the fuel tank (24) to the trailer frame.

(8) Inspect the fuel level gage for free

operation of the float and proper registration of the

Remove the fuel tank.

level indicator. Replace gage if damaged.

(5) You can now disassemble the fuel tank as

c. Reassembly and Installation. Reassemble and

shown in figure 4-3. Note that the liquid level gage

i n s t a l l the fuel tank fuel lines, and fittings in

(23) is threaded into the tank and that you can

remove it by turning counterclockwise.

r e v e r s e order of removal and disassembly. Pay

b. Cleaning and Inspection.

particular attention to the following:

(1) Be sure that the drain plug (1, figure 4-3)

Clean all parts in a well-ventilated area.

is installed and all fittings are tightened properly

Avoid inhalation of solvent fumes and

before you fill the tank with fuel.

prolonged exposure of the skin to

( 2 ) After you have partially filled the tank

cleaning solvent. Wash exposed skin

with fuel, check for leaks of the system. Correct any

thoroughly.

leaks noted.

(1) Steam-clean the inside and outside of the

4-19. Fuel Pump and Strainer

fuel tank. Thoroughly flush with cleaning solvent

(fed. spec. P-D-680).

NOTE

You shall remove the fuel pump only when required

to replace a leaking gasket or when tests indicate that

If conditions require emergency fuel

the fuel pump is faulty.

tank repairs by welding or other

a. Testing. To test the fuel pump for faulty

methods involving heat or flame, all

operation, proceed as follows:

gasoline fumes must be purged from

( 1 ) With engine off, assure that it will not

the tank before commencing repair.

s t a r t b y t r i p p i n g o i l p r e s s u r e s a f e t y switch.

Applying heat or flame to a fuel tank

Disconnect fuel line at carburetor.

containing gasoline residue may result

(2) Turn the engine over with the starter. A

in a violent explosion, causing injury or

properly operating fuel pump will squirt out fuel

death to maintenance personnel.

w i t h some force. Replace a faulty operating or

(2) Inspect the fuel tank for cracks, dents,

damaged fuel pump.

damaged threads, and broken weldments. Replace

b. Removal and Disassembly. R e m o v e a n d

a damaged fuel tank.

disassemble the fuel pump and fuel strainer

(3) To remove embedded material from the

following the sequence indicated in figure 4-4. Pay

strainer, you can use a soft-bristled brush.

particular attention to the following:

(4) Clean all fuel lines and fittings with

cleaning solvent (fed. spec. P-D-680). You should

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