Overview

The Simrad 000-13697-001 is a mechanical autopilot drive unit (SD10) that pulls a steering cable to move a rudder quadrant or tiller arm on sailboats in the 25 to 37 ft range. It runs on 12 V DC and combines the drive motor, electromagnetic clutch, and an integral rudder feedback module in one assembly.

With over 180 kg (400 lb) of cable thrust and a typical hard-over to hard-over time of 12 to 15 seconds, it suits many mid-size cruising sailboats up to about 6500 kg fully laden. Maximum stroke is 305 mm (12 inches), which helps when matching common quadrant travel without running out of movement.

This drive is intended to pair with a Simrad NAC-2 autopilot computer. Installation requires access to the steering gear, since the steering cable and connection hardware transmit the push and pull directly to the quadrant or tiller arm.

Key features

• 12 V DC mechanical sailboat drive for Simrad NAC-2 autopilot computers
• Boat fit range: 25 to 37 ft length, up to about 6500 kg fully laden displacement
• Over 180 kg (400 lb) cable thrust with typical hard-over to hard-over time of 12 to 15 seconds
• Electromagnetic clutch allows hand steering when disengaged
• Integral rudder feedback module built into the drive unit
• 305 mm (12 in) maximum stroke to cover common quadrant travel
• Adjustable thrust limiter and a quick-release connection at the steering end for manual control options

What’s included

• SD10 mechanical drive unit
• 2 m (6 ft) steering cable
• Universal connection kit for quadrant or tiller arm attachment

Compatibility and fit

This drive is meant for sailboats with a steering quadrant or tiller arm where a cable pull can be attached through the supplied connection hardware. If your boat has limited access around the steering gear, plan the mounting location and cable run first so the drive has room for the cable entry and exit path.

It is a 12 V unit. Boats with 24 V house systems typically handle this by supplying a dedicated 12 V feed for the autopilot drive circuit.

Installation and setup

The drive unit can be mounted at various angles, as long as the structure is solid and the cable run stays smooth. Keep bends gentle, avoid stacking multiple tight turns, and allow enough clearance for the steering mechanism through full travel. The connection kit should be mounted to stable structure so the steering cable thrust stays aligned with the quadrant or tiller arc through mid-stroke.

Some installs benefit from swapping the cable entry and exit routing to get a cleaner run. Steering direction can be corrected during autopilot commissioning so the pilot steers the correct way.

Electrical and system integration

Electrical integration is straightforward: the autopilot computer supplies motor and clutch power, and the rudder feedback signal returns to the pilot for accurate rudder position tracking. Use a clean 12 V feed with appropriate circuit protection and keep connections dry, supported, and strain-relieved to hold up to vibration and humidity.

Use on board

This drive is a good match for coastal cruising and longer passages where you want a below-decks mechanical drive with built-in rudder feedback, without adding a separate feedback sensor on the quadrant. It is also a sensible fit for boats that need a manual steering escape route, since the clutch and mechanical disconnect options let you get back to hand steering quickly when needed.

Maintenance and care

The steering cable is a wear item. Cable life depends heavily on routing and loads, but planning on replacement around 150 to 200 hours of use or about every two seasons is a practical baseline. Grease the connection kit at the grease nipples on installation and at regular intervals, and consider carrying a spare steering cable for extended cruising.