Reversible Plough Reversal Sticking: Check the Hydraulics and the Mechanics

The heart of a reversible plough is the flip mechanism: the ram that rotates the frame between passes. When the reversal slows, sticks or stops halfway, the plough loses its main advantage. Most reversal problems start slowly, and they fall into two groups: hydraulic faults and mechanical faults. Working through them in order keeps the plough flipping reliably and avoids a breakdown in the middle of a paddock.

Start with the hydraulic supply

Slow reversal often means the oil is not reaching the ram at full flow. Check the tractor hydraulic oil level and condition, and confirm the spool valve returns to the right position. Restriction in hoses or a weak pump slows the flip to a crawl. If the reversal speed is uneven from one direction to the other, the issue usually sits in the valve or the ram seals rather than the pump.

Inspect the ram and seals

A ram with worn internal seals drifts and hesitates, because oil leaks past the piston. Look at the ram rod for scoring, and check the rod wiper and gland seals for weeping oil. A bent or scored rod does not seal properly, and the reversal loses power. Rebuild kits for the ram are far cheaper than a replacement cylinder, and they restore full flip speed.

Check the pivots and linkage

Mechanical stiffness slows the flip too. Pivot bearings on the main rotation point rust and seize without grease, and bent linkage arms bind in their brackets. Grease every pivot nipple, and work the flip by hand when the tractor is off to feel for stiff spots. A pivot that grinds or sticks when moved slowly needs cleaning, greasing or bearing replacement.

Watch for hydraulic oil aeration

If the reversal judders or jerks, air in the hydraulic circuit is often the cause. Bleed the system according to the tractor manual, and check the oil level when the system is warm. Aeration usually comes from low oil or a leak on the suction side, so fixing the level and any suction leak settles the judder within a short run.

Test the flip under real load

Once the suspected cause is fixed, run the plough through several flip cycles with the implement lowered and raised. The reversal should be smooth and fast in both directions, with no drift in the held position. A plough that flips cleanly on every pass saves time on headlands and keeps both sets of bodies working evenly.

References

BROWN R T, DAVIES M K. Failure modes of reversible plough reversal mechanisms[J]. Biosystems Engineering, 2020, 198: 90-99.

Brown, R. T., and M. K. Davies. "Failure Modes of Reversible Plough Reversal Mechanisms." Biosystems Engineering, vol. 198, 2020, pp. 90-99.

Brown, R. T., & Davies, M. K. (2020). Failure modes of reversible plough reversal mechanisms. Biosystems Engineering, 198, 90-99.