Great Plains John Deere 455 30' Flat Fold Markers - Manual (Page 13)

10/17/2002 205-046M
11 Hydraulic System
Adjusting The Hydraulics
1. Be sure tractor hydraulic reservoir is full.
2. With the markers in field position, crack the
hydraulics hose fittings located at the base
end of one of the cylinders. With the tractor at
an idle speed, activate the tractor hydraulics
valve until hydraulic oil seeps out around the
hose end. Tighten the hose end fittings. Re-
peat this process for the hose at the rod end
of the cylinder. Crack the fittings on the back
side of the sequence valve until hydraulic oil
seeps out. Tighten and repeat for the oppo-
site cylinder.
3. Cycle each cylinder 3 or 4 times slowly. Both
arms should move to the vertical position on
the first move and then they should lower and
raise alternately as the hydraulic lever is oper-
ated.
4. Fold and unfold the marker(s) slowly in order
to work all the air out of your marker hydrau-
lics. Use caution when folding and unfolding
the marker for the first time, and check for
pinching and kinking of hoses.
!
CAUTION
Never allow anyone near the drill when cycling the
markers.
5. The marker hydraulic system is equipped with
needle valves to control how fast each marker
operates. The needle valves are built into the
sequence valve body. There are two hex ad-
justment heads, one for raising the markers,
and one for lowering the markers. These are
stamped in the valve body. To adjust the
speed of each marker, screw the needle valve
clockwise to adjust the raise or lower marker
speed to a low setting. Fold the marker up and
down a few times and recheck for pinching
and kinking of hoses. With the tractor engine
at an operating rpm, adjust the needle valve
to limit the marker to a safe operating speed.
Excessive folding speeds can cause marker
damage.
!
CAUTION
Excessive folding speeds can cause marker damage!
!
CAUTION
Escaping Fluid under pressure can have sufficient
force to penetrate the skin. Check all hydraulic lines
and hoses before applying pressure. Fluid escaping
from a very small hole can be almost invisible. Use pa-
per or cardboard, not body parts, to check for suspect-
ed leaks. If injured, seek medical assistance from a
doctor that is familiar with this type of injury. Foreign
fluids in the tissue must be surgically removed within a
few hours or gangrene will result.
NOTE: JIC fittings do not require high torque. JIC
and O-Ring fittings do not require sealant. Always
use liquid pipe sealant when adding or replacing
pipe thread fittings. To avoid possible danger of
cracking hydraulic fittings from over tightening,
DO NOT use plastic sealant tape.
Hydraulic System