Vedeneyev M-14P, Maintenance Manual

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3. LUBRICATION SYSTEM UNITS
3.1. OIL PUMP MN-14A
The oil pump is intended to deliver oil from the tank to the engine oil gallery and to scavenge oil from the
oil sump to the tank.
Specifications
Direction of rotation ......................................... ................................... Left
Drive transmission ratio ....................................................................... 1.125
Pump drive shaft speed of rotation:
Maximum (for up to 10 min) .................................. ............................. 3319 r/min
Minimum ..................................................... ....................................... 580 r/min
Working fluid ................................................. ..................................... Oil MS-20 GOST 21743-76
Pump delivery at drive shaft speed of 2400 r/min:
Delivery section:
At oil pressure of (5±0.2) kgf/cm in oil gallery and oil temperature of 50 to 60 °G ........................... 516 1/h
At cap plugged and outlet backpressure of (6±0.2) kgf/cm
2
........................................ Not less than 900 1/h
Scavenging section at outlet backpressure of (1±0.2) kgf/cm
2
and oil temperature of 75 to 125 °C……………Not
less than 1460 1/h
The oil pump comprises a housing, drive shaft, driven shaft with gear rims, four gears, reducing and check
valves, packing gland and other parts.
The pump housing assembly is a magnesium casting comprising scavenging section housing (9) (Ref.
Fig. 2), delivery section housing (4), upper cover (14) and lower cover (2).
The scavenging section housing has two wells accommodating gears (10) and (12), holes for studs and
shafts, holes for inlet and outlet of oil and locating recesses.
The scavenging housing bottom makes the partition between the scavenging and delivery sections.
Delivery section housing (4) has two wells for gears (6) and (15), oil inlet and outlet holes, holes with
pressed-in bronze bushings serving aa shaft lower bearings, flange with holes for studs (7) adapted to attach the
housing to the rear cover and six studs (18) for attachment of lower cover (2).
The lower flange wells accommodate delivery section gearing, reducing and check valves and oil pressure
measuring connection.
Housing upper cover (14) has a locating collar, two holes with pressed-in and locked bronze bushings
being the pump shaft bearings and four holes for passing studs (11) (Ref. Fig. 3) which secure the pump
housings.