Troubleshooting Hydraulic Steering Systems

Besides light and nimble controls, a major benefit of a hydraulic steering system is that very little goes wrong with it. Check periodically for leaks and top off the fluid and it shouldn’t give you any problems.

On the rare occasion that it does, the problem is usually very easy to fix. Here are some of the most common problems boaters encounter with hydraulic steering systems and how to resolve them.

Hydraulic Steering Issues

Unresponsive Steering – If the steering feels soft or mushy, it’s usually a sign of air in the hydraulic system or the hydraulic fluid needing a change. Bleeding the system will purge it of the old hydraulic fluid and any air in it. To inspect the fluid, dip a screwdriver or pen into the helm’s reservoir and check that it’s odorless and clear. If it smells bad or looks discolored, the system needs to be bled.

Steering Responds Well in Only One Direction – The relief valve for the hydraulic helm pump is stuck. To fix it, simply turn the wheel to hard full lock and continue applying pressure until the relief valve opens. Repeat this process in the other direction. Once the relief valve is free, it should fix this steering issue. 

Steering Slow or Won’t Turn All the Way – Indicative of leaking steering cylinder seals. Check the seals for signs of escaping fluid, and make sure the cylinder shaft is dry and free from fluid when exposed from the cylinder body. Replace the cylinder’s seals if any fluid is found.

This issue may also be caused by the steering cylinder itself. Remove the cylinder shaft, and inspect it and the inside of the cylinder for any corrosion or damage. Thoroughly clean (or replace) both and reassemble with new seals.

Hydraulic Fluid Leak at Cylinder – A definite sign of worn cylinder seals. Replace the seals immediately, and check the steering shaft and inside the cylinder while you’re at it. 

Hydraulic Fluid Leak from Helm Fill Cap – A common issue that happens in hot weather due to thermal expansion of the fluid within the reservoir. It’s recommended that all helms are filled right up to the bottom of the filler hole, with the fluid in horizontally mounted helms never falling lower than 1/4" from the filler hole; and fluid in helms mounted at 20° (or with a vertical wheel shaft) never falling lower than 1/2" of the filler hole.

Other Common Boat Steering Problems

The hydraulic steering system is often not the problem with a boat’s steering. One common issue is the steering requiring a lot of force and feeling heavy, particularly at speed. Typical non-hydraulic issues that cause heavy steering include:

Steering Wheel Size. The steering wheel is too small and needs to be replaced with a larger one.

Pivot Tube. The pivot tube, around which the outboard pivots from port to starboard, is dirty or corroded. Remove the motor, then clean and re-grease the pivot tube.

Prop Torque. The torque of the propeller in the water is causing the boat to naturally turn in a certain direction. Adjust the trim tab anode and/or trim tabs to compensate accordingly.