7085-S power assist


The Kobelt 7085-S power assist steering cylinders are controlled via inputs from fluid pressurized by a helm pump but are powered by a machine-driven pump.

This configuration enables responsive steering while requiring minimal human effort. In the case of a failure of the machine-driven pump the unit automatically switches to manual mode which allows for
steering via helm pump pressure only.

Kobelt 7085-S cylinders consist of three main subunits which are the main cylinder, the control cylinder, and the valve.

7085-S overview

7085-SB cylinder overview

Constructed in corrosion resistant materials and finishes, the 7085-S power assist is suited for harsh marine applications. When a single balanced cylinder is not sufficient to provide the required rudder torque, it can be installed in a twin cylinder configuration whereby the 7085-SB would serve as a master with a 7085-B second cylinder of the same stroke.

Unbalanced cylinders always should be installed in a twin cylinder configuration

For balanced, the 7085-S has the following stroke and displacement ranges, assuming a single cylinder at 800 psi (55 bar) at a 35º rudder angle / 45º rudder angle.

Torque: 4,580 to 9,200 lbs. ft. (633 to 1.272 kg/m)   3,270 to 6,500 lbs. ft. (452 to 899 kg/m)

Stroke: 10″ to 20″ (254 mm to 508 mm)
Displacement: 78.5 in3 to 157 in(1.286 cm3 to 2.572 cm3)


  • LR type approved
  • Constructed from corrosion resistant materials for harsh environments
  • Input from helm pump and/or an electric steering pump
  • Compact design
  • Available in balanced and unbalanced models
  • Available in four different cylinder strokes

For this cylinder is a repair kit available.

Features & Options

Available in both Balanced & Unbalanced Versions
Bronze & Stainless Steel Construction