Bleeding cylinders and lines, Caution – MacDon PW8 Pick-Up Header User Manual
Page 167
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Bleeding Cylinders and Lines
In order for the hydraulics to perform properly, all or most of the air must be removed from the system. The following
procedure is the simplest method for bleeding the hydraulics.
The hydraulics should be bled after initial installation, if the unit has been idle for a significant period of time, or 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 burned.
1. Fully raise the hold-down with the combine reel lift
control.
2. Engage the hold-down safety props. Ensure that the
prop is fully rotated over-center so that it remains
engaged.
3. Lower the hold-down onto the safety props. (This
relieves the hydraulic pressure in the lines).
Figure 4.165: Hold-Down Safety Props
4. Hold a plastic container up to the bleed plug.
5. Loosen the bleed screw with a 1/4 inch wrench.
6. Activate the lift control. The hold-down may lift slightly,
and a stream of oil will come from the bleed screw.
7. Bleed oil until it is a steady clear stream. Release lift
control, and tighten the 1/4 inch bleed screw.
8. Fully raise the hold-down.
9. Disengage the safety props.
10. Lower the hold-down.
Figure 4.166: Bleed Cylinders
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