Great Plains YP1220 Operator Manual - Manual (Page 36)

32 YP1220 Great Plains Manufacturing, Inc.
401-506M 03/14/2012
Marker Operation
Before operating markers, make sure they are properly
bled as described in “Bleeding Hydraulics” on page 55.
Dual markers are equipped with a sequence valve to
control lift sequence. Starting with both markers up, the
sequence is:
1. If the planter is equipped with an auxiliary hydraulic
system, set the selector valve (found near the
sequence valve at the marker base on the left wing)
to “Marker”.
2. Activate tractor hydraulic lever; right marker lowers
while left marker stays up.
3. Reverse hydraulic lever; right marker raises while left
marker stays up.
4. Activate hydraulic lever; left marker lowers while right
marker stays up.
5. Reverse hydraulic lever; left marker raises while right
marker stays up.
6. Pattern repeats.
Folding speed of dual markers is adjusted with adjust-
ment screws on sequence valve body. Because exces-
sive folding speed may damage markers, adjust markers
to a safe folding speed according to “Marker Adjust-
ments” on page 41.
Note: To get both markers in the lowered position at the
same time, activate hydraulic lever to lower one
marker. After marker is lowered, move lever to
opposite position then quickly reverse lever and
hold until other marker is lowered.
Re-phasing Lift System
Over a period of normal use the cylinders may get out of
phase. This will cause some planter sections to run
higher than others. If this is the case, it will be necessary
to re-phase lift cylinders. NOTE: Lift cylinders can only
be re-phased when planter is unfolded.
To re-phase cylinders:
1. Raise the implement completely and hold the
hydraulic remote lever on for several seconds until all
cylinders are fully extended. Do this every 8 to 10
times you raise planter out of ground.
2. When all cylinders are fully extended, momentarily
reverse hydraulic remote lever to retract system
1 ⁄
2
in
to maintain levelness.
Re-phasing Fold System
Over a period of normal use, the cylinders may get out of
phase. This is evident by wing gauge wheels not running
in their fully rotated positions in front of the planter.
Note: Planter must be folded to re-phase fold system.
Refer “Unfolding the Planter” on page 24, for
instructions on re-phasing fold system.