MacDon PW7 Pick-Up Header - Manual (Page 63)

SECTION 7 – SERVICE
Form 169149 Revision E 57
Installing the 1/16-inch diameter hole
orifice will likely prevent the master
cylinder from lagging.
F) Bleeding the Hydraulics
In order for the hydraulics to perform
properly, all or most of the air must be
removed from the system. The following
procedure provides the easiest method of
bleeding the hydraulics. The hydraulics
should be bled after initial installation, if the
unit has sat for a significant period of time,
and if adjustments are needed to the
hydraulics.
CAUTION : High-pressure
hydraulic oil can cause serious
injuries such as burns, cuts, and
tissue damage! Always take
precautions when working with hydraulic
oil. Wear safety goggles, gloves and thick
clothing. Seek immediate medical
attention if cut or burnt.
a) The hold down is controlled using the
reel lift control located in the combine
cab. Fully raise the hold down.
b) Engage the hold down safety locks.
Ensure that the lock is fully rotated over
center so that it will not slip forward.
c) Lower the hold down so that it comes to
rest on the safety locks. (This serves to
relieve the hydraulic pressure in the
lines).
d) Hold the plastic pail so the lip of the pail
is underneath the bleed plug and so that a
stream of oil shooting out of the plug will
go into the pail.
e) Loosen the small bleed screw on the end
of the bleed plug with a 1/4-inch wrench.
f) Have someone activate the hydraulics. The
hold down may lift slightly and a stream of
oil will come from the bleed screw.
g) Run oil from the bleed screw until it is a
steady clear stream. Have the operator stop
activating the hydraulics and tighten the
1/4inch bleed screw.
h) Fully raise the hold down again.
i) Disengage the safety locks.
j) Lower the hold down.
Bleeding of Hydraulics
P00696
P00696