Overview

The Raymarine M81130 is a 12V Type 1 mechanical linear autopilot drive for mechanically steered boats up to 11,000 kg or 24,000 lb displacement. Mounted below deck, it drives the rudder directly by pushing on a tiller arm or rudder quadrant, making it a practical match for sailing yachts and mechanically steered vessels that need an autopilot drive kept out of the cockpit.

This short-shaft drive has a 300 mm (12 in) maximum stroke, 295 kg (650 lb) peak thrust, and an 11-second hard-over to hard-over time under no load. It uses an electric motor with an electromagnetic fail-safe clutch, a high-tensile belt drive, and an epicyclic gearbox, so hand steering remains smooth when the autopilot is in standby.

Key features

• 12V Type 1 linear drive for existing mechanical steering systems and below-deck autopilot installations.
• Rated for boats up to 11,000 kg (24,000 lb) displacement when correctly matched to the vessel and steering geometry.
• 300 mm (12 in) maximum stroke supports short-shaft mechanical linear drive installations.
• 295 kg (650 lb) peak thrust and 735 Nm (6,500 lb.in) maximum rudder torque for direct rudder actuation.
• Electromagnetic fail-safe clutch releases the drive when the autopilot is disengaged, keeping manual steering free from unnecessary drag.
• Works with Raymarine ACU-200 actuator control units in Evolution autopilot systems.
• Average power consumption of 18-36 W helps manage load on a 12V house or electronics supply.

Installation and fit

The fixed end of the drive mounts to a strong structural point below deck, while the moving end connects to the rudder stock or quadrant through an independent tiller arm. The steering system must be able to back-drive from the rudder, and accessory fittings from the steering manufacturer may be needed to complete the installation.

Because the drive works directly on the rudder rather than on the helm, careful alignment and correct tiller-arm geometry matter. It is best suited to boats where there is enough access around the rudder quadrant or tiller arm for the full 300 mm stroke and for service inspection after installation.

System compatibility

This unit is for 12V DC autopilot systems and is commonly paired with an ACU-200 as part of a Raymarine below-deck autopilot setup. It is the drive unit only, so the autopilot computer, control head, sensor core, cabling, and any steering-specific hardware must be matched separately to the vessel.

Use on board

The M81130 suits owners who want below-deck steering assistance for cruising, passage making, or sail handling when the helm needs to stay steady for long periods. Its low backdrive force is especially useful on boats where the helm is still used manually between autopilot runs.