Before Operation Services

TM 5-4320-273-14

The selector valve (1)

a. Prime the pump with the liquid to be pumped by

n. Fuel Source Selector Valve.

controls the source of fuel to the engine. In the OFF

closing the suction valves, removing the primer fill

position it shuts off the fuel source. In the TANK

cap (3, fig. 1-2), and filling the pump housing to the

position it connects the engine fuel system to the fuel

level of the cap. Make sure the drain valve at the bot-

supply in the fuel tank. In the AUX position it con-

tom of the housing is closed,

nects the engine fuel system to an auxiliary external

fuel supply, if connected.

o. Air Eliminator Vent Valve. The vent valve (2)

serves to vent off entrapped air during the priming

WARNING

cycle and is normally left open during operation.

p. Check Valve Override Handle. The check valve

After removing the priming cap and fill-

override handle (3) adjusts to the opening and closing

ing the pump casing with the product to

of the check valve. Normally, the check valve closes

be pumped, check the snap-in gasket in

automatically when the pumping operation is discon-

the cap to be sure that it is present and

tinued; this retains enough fuel in the pump and suc-

that it is serviceable (no dents; cuts,

tion hose for priming the pump in subsequent

abrasions). Remove and replace as

operations. The check valve throttle can be manually

necessary.

opened to drain the liquid back through the pump

and the suction hoses when required.

When the casing has been filled, place

q. Suction and Discharge Gate Valves. The suction

the cap on the male quick disconnect

and discharge gate valves (4 and 5), located on the

adapter and raise the cam levers on the

suction and discharge manifolds, are designed to con-

cap to the fully locked (vertical) posi-

trol the flow of fuel in the system.

tion.

Bind the cap cam levers together in the

locked position with soft wire or heavy

2-3. Before Operation Services

twine in order to eliminate any possibili-

Before operating the pump assembly, you must en-

ty of their release due to vibration. This

sure that installation instructions have been followed

procedure must be followed each time

and that inspection and servicing has been per-

the pumping assembly is primed.

formed. In addition, inspect all the suction and

discharge hoses. Ensure that each connection is

properly secured and that the hoses are in-

b. Open the

air eliminator valve (2, fig. 1-2).

dependently supported near the pump. Arrange the

C. Although

electric start engines do not require

hoses as straight as possible. Required bends should

hand priming,

it is a good practice to prime the fuel

be made with a long radius.

system if the

engine is being started for the first

2-4. Starting

CAUTION

Starting a dry pump may damage the

pump shaft seal.

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