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Agrowplow deep rippers with the #9 hydraulic shank, including the AP51, AP71, AP81, and AP91.
The principals can also be applied to the #9 hybrid shank on the AP11 and AP31.
Plough hydraulic systems require consistent hydraulic pressure to ensure the shanks break out at the correct pressure. Air can be introduced into the system through normal use and should be purged regularly.
As air builds in the hydraulics, it causes the shanks to break out more frequently. It can also cause premature wear in the hydraulic cylinders and in some cases cause the end caps on the cylinders to break.
Air should be purged from the hydraulics as part of your pre-season setup and as part of your daily pre-operational checks. If done regularly, this process should only take a few minutes prior to using the ripper.
Engage the tractor park brake and raise the shanks off the ground. Set the hydraulic pressure to 0psi. Apply steady pressure with your foot to the shank blade. A correctly primed hydraulic system will have very little travel. If you can break the shank back with just your weight alone, this indicates air in the hydraulic system.
Check the hydraulic cylinder end caps. If the end caps are broken this also indicates air in the hydraulic system.
Ensure your tractor and plough are parked on flat, level ground such as turf with the tractor park brake engaged. Do not perform this operation on a hard surface such as concrete, as this will not provide enough surface for the plough blades to catch and gain sufficient leverage to break back while still supporting the weight of the frame.