TM 55-1905-219-14-8
4-7.5A. PRIMING PUMP - MAINTENANCE INSTRUCTIONS.
a. The priming pump is a rotary vane type pump. The magnetic clutch is mounted on the priming pump
shaft. The priming pump is driven by a sheave, part of the magnetic clutch, which is driven by the engine fan
belt.
b. The intake side of the priming pump is connected to the intake side of the fire pump. There is a check
valve in this line to prevent air from being sucked through the priming pump once the pump has been
pressurized.
c. With the engine running, water discharge valve closed, and the prime pushbutton depressed, the magnetic
clutch is engaged and the priming pump evacuates the air from the fire pump housing and the suction hose. If
priming pressure is lost, a pressure switch located on the discharge side of the fire pump will automatically stop
the engine. The pressure switch is preset for 10 to 15 psi (68.9 to 103.4 kPa).
This task covers:
a. Removal
d. Inspection
g. Repair
b. Disassembly
e. Reassembly
c. Cleaning
f. Installation
INITIAL SETUP
Test Equipment
References
NONE
NONE
Equipment
Special Tools
Condition Condition Description
Arber press
NONE
Lead hammer
Spanner wrench
Material/Parts
Special Environmental Conditions
General purpose cleaner
NONE
Silicone compound
MIL-S-8660
Sulphamic acid PS-120
Personnel Required
General Safety Instructions
1
Observe WARNING in procedure.
4-330