Installation Of Hydraulic Pump; Priming Hydraulic Pump - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
k.
Replace the four socket head cap screws (12) that secure the rear side, centerplate and drive side
assemblies together. Torque the socket head cap screws and locknut to 60 inch-pounds.
1.
When the pump is assembled, turn drive shaft by hand to make sure the pump turns freely. If
there is any sticking or binding at all, disassemble pump and determine the trouble. Do not apply power to
the pump until it turns freely by hand.
NOTE
If possible run pump at rated speed while gradually increasing the
pressure up to rated pressure by the end of a thirty minute period.
6-156. INSTALLATION OF HYDRAULIC PUMP.
a.
Place a new gasket on the base of the housing.
b.
Install pump on the housing.
NOTE
When installing pump keep the drain fitting facing to the lower
right, in the downward position.
c.
Line shaft up with the gear inside of the housing.
d.
Install flat washers, lock washers and nuts on the base of the pump and tighten.
e.
Install the two hydraulic hoses and prime the pump before completing the hookup to the firewall
fittings in accordance with Paragraph 6-157.
f.
Check to be sure that system reservoir contains the required amount of clean fluid.
g.
Change system fluid filters, in accordance with Paragraph 6-148.
h.
Check to be sure that system reservoir contains the required amount of hydraulic fluid.
6-157. PRIMING HYDRAULIC PUMP. The following instructions for priming the hydraulic pump assures
that the pump will not be operated in a dry condition and shall be followed whenever a pump is serviced or
replaced.
a.
Remove the hydraulic suction and pressure lines from the firewall fittings.
b.
Install caps on suction and pressure fitting at the firewall to prevent the loss of fluid prior to the
hookup of the hydraulic lines.
c.
Holding both lines at a level higher than the pump, pour hydraulic fluid, MIL-H-5606, into the
lines.
d.
Remove one cap at a time from the firewall fittings and connect the appropriate line to the
fitting, trying not to spill any of the hydraulic fluid previously put into the lines.
e.
After the engine has been operated, check the hookups for leaks.
Reissued: 9/23/80
HYDRAULIC SYSTEM
2D9