TM 9-2330-356-14
which valves, couplings, etc. must be removed in order to
remove the piping.
(3) Tag and disconnect any nylon tubing from the
b.
Installation.
a. Precheck Circuit (M970 and M970A1)
TA099875
operations. The circuit includes the precheck valve, the
float valve, and all necessary tubing and fittings
a.
Lubrication. Lubricate the intermediate housing
(1) Precheck Valve.
lubrication instructions and correct lubricant.
(a) In the open position, this valve allows
fluid from the inlet of the 4-inch control valve to reach the
Priming. Whenever pump has lost its prime,
b.
(b) The fluid raises a float in the float valve
bottom of fill port with the type of fuel being transported
in the semitrailer tank.
(c) With flow shut off, the pressure in the
line to port Y is equalized. A spring in the 4-inch control
valve then closes the 4-inch control valve and stops bottom
load operations.
(2) Float Valve.
(a) This valve automatically closes the
4-inch control valve when fuel level inside the tank rises to
a predetermined level during bottom load operation.
(b) With precheck valve in the closed
position, fluid rises in the tank until it reaches the float
the float, which shuts off the fluid entering in port Y of the
float valve.
(c) With flow shut off at port Y, the
pressure in the line to port Y is equalized. A spring in the
TA099876
4-inch control valve then closes the 4-inch control valve
and stops the bottom load operation.
Precheck and Load/Unload Circuit (M967,
b.
Removal.
a.
used to check the float valve for proper operation
(para 2-11) during bottom load operations. In
addition, a
(1) Review General Instructions before remov-
load/unload valve is added to the circuit to shut off 4-inch
control valve during bulk delivery operations. The circuit