1205NT
Preparation and Setup
16
3/7/19
150-131M
Rephasing Cylinders
The lift cylinders may, after a period of time, get out of
time or phase. The effects of this can be seen when one
side of the drill is running too low or too high because its
lift cylinder is either over extended or not retracted
compared to the other lift cylinder.
To rephase the cylinders, raise drill completely and hold
tractor hydraulic lever on for a few seconds to give
cylinders time to rephase.
Each time drill is raised out of ground momentarily
reverse hydraulic lever immediately after rephasing to
allow cylinders to retract about 1/2 inch. This will help in
maintaining a level drill.
Note: Understand that having cylinders become
gradually out of time is different than having air
trapped in the system from improper bleeding.
Each condition is corrected differently.
Bleeding Hydraulics
Escaping fluid under pressure can have sufficient pressure to
penetrate the skin causing serious injury. Avoid the hazard by
relieving pressure before disconnecting hydraulic lines. Use
a piece of paper or cardboard, NOT BODY PARTS, to check
for leaks. Wear protective gloves and safety glasses or
goggles when working with hydraulic systems. If an accident
occurs, immediate medical attention from a physician
familiar with this type of injury.
Check that tractor hydraulic reservoir is full.
The drill lifting system is equipped with rephasing type
hydraulic cylinders that require a special procedure for
bleeding air from the hydraulic circuits. Read and follow
this procedure carefully. Rephasing type cylinders will
not function properly with air in hydraulic circuit.
1. Check hydraulic fluid in tractor reservoir and fill
reservoir to proper level. Drill-system capacity is
about 1 gallon. Add fluid to system as needed. A low
reservoir level may draw air back into the system,
causing jerky or uneven cylinder movements.
2. With drill attached to tractor, jack drill up and support
frame at ends near gauge wheels.
3. With drill raised and supported, unpin cylinders from
gauge wheel arms and frame. Turn cylinders “rod
end up”. Wire or otherwise safely support rod ends
higher than base ends.
Note: In order to prevent trapped air pockets, rod end
must be higher than any other part of cylinder
during bleeding operation.
4. With tractor engine idling, engage tractor hydraulics
to extend cylinder rods. When cylinder rods are
completely extended, hold remote lever on for one
minute.
5. Retract cylinders. Extend cylinders again and hold
remote lever on for one more minute. Repeat this
step two more times to completely bleed system.
6. Repin cylinders to drill frame and gauge wheel arm
with transport cylinder locks in place. If any air still is
trapped in either cylinder, the cylinder will have a
spongy, erratic movement and drill will not raise
evenly. If necessary, repeat bleeding process.
7. Refill tractor hydraulic fluid reservoir to its proper
level.
Note: After the drill is raised, a slight settling will occur
due to the action of the rephasing cylinders.