MacDon PW7 Pick-Up Header - Manual (Page 58)

SECTION 7 – SERVICE
Form 169149 Revision E 52
B) Hydraulic Cylinder(s) Replacement
The hold down employs a single-acting master
and slave circuit for raising and lowering the
hold down. The operation of the lift can be
adversely affected by factors such as air in the
system. It is suggested that the following
procedure be used to ensure proper operation of
the hold down when servicing the unit.
Removal/Installation Procedure
a) Lower the hold down completely down,
shut off combine and remove key.
b) Release all hydraulic pressure in the
system.
c) Remove all hydraulic hoses from the
cylinder(s) being removed. Be sure to
have a container and rags to catch any
escaping hydraulic oil.
d) Remove the two hitch pins and washers
that hold the cylinder on the pickup.
e) With the help of a second individual who
is slightly lifting up the hold down, pull
off the cylinder and install the new one.
NOTE: There should be a washer on the
outer sides of the cylinder.
f) Install the washers and hitch pins.
g) Complete Fitting Transfer/Installation if
replacing cylinder.
Fitting Transfer/Installation
You will now have to either transfer the old
fittings over from the removed cylinder or install
the new fittings onto the new cylinder. The
following will instruct you on the proper
procedure:
Master Cylinder
a) Remove the two 90-degree elbows and
the orifice from the old master cylinder.
b) Screw the orifice into the lower port of
the master cylinder. Turn until the orifice
bottoms out. Then screw one ORB/JIC 90
degree elbow into the lower port of the
master cylinder. Continue screwing in the
elbow until you feel a slight resistance
then stop. Orient the elbow tip upward
approximately 30 degrees outward and
tighten the jam nut.
c) Screw in the second ORB/JIC elbow into
the upper port of the master cylinder until
you feel a slight resistance then stop.
Orient the tip of the elbow straight toward
the cylinder rod and tighten the jam nut.
d) Connect the hold down hose to the upper
90-degree elbow on the master cylinder.
When tightening the hose ensure the hose
goes up from the elbow and does not fall
to the side.
e) Connect the header hose to the lower 90-
degree fitting on the master cylinder.
Master Cylinder
Note: The ports of the master and slave
cylinders point downwards on a
SwathMaster pickup and face upwards on
a Rake-Up pickup.
P00691