Great Plains 4000TT Operator Manual - Manual (Page 46)

Section 2: Hydraulics
Table of Contents ► Great Plains Mfg., Inc.
Series I 1000TT - 4000TT Turbo-Till 586-043M 1/25/2008
44
17’, 22’ & 30’ Hydraulic Down Pressure Preparation and Setup
Note: This setup procedure is for tractors with closed-center or pressure compensated flow
hydraulic systems. Open center hydraulics not supported.
1. Adjust the bypass/pressure reducing
valve by turning knob (1), Figure 1,
clockwise all the way in and then backing
out 1 full turn.
2. On tractor, adjust flow-control valve to low
side of flow rate. NOTE: The faster the
flow of oil through the system the greater
potential for oil heating, premature wear
or tractor damage.
3. Lock the fold hydraulic lever for
continuous downward oil flow.
4. Adjust bypass/pressure reducing valve
knob (2) on implement so the pressure
gauge reads 1200 psi. Never exceed
1400 psi.
5. While watching pressure gauge, slowly open
valve knob (1) until gauge reads 1100 psi.
Pressure might rise and then fall off as knob
is opened. If pressure exceeds 1400 psi
during this step, the tractor flow is too high,
reduce tractor flow. Lock valve knob (1) at
1100 psi.
6. Finally adjust valve (2) to the desired wing
down pressure setting of 300 to 400 psi.
Never exceed 700 psi.
7. In field operation, Lock the fold
hydraulic lever for continuous
downward oil flow. If wings are
running too high, increase pressure
setting, knob (2), to level machine. If
center is too high, decrease pressure
setting with knob (2) on valve.
8. Caution: Never leave tractor valve
centered when unfolded with machine
in motion. Machine damage may occur
when wings flex up or down (see page
69).
Figure 1
!