Short type 2 mechanical linear actuator, 300mm, 12V

This is a 12V autopilot actuator designed specifically for heavy-displacement sailboats. It connects directly to the tiller quadrant or rudder quadrant arm to control the boat's heading.

Type 2 hydraulic ram delivers significantly higher thrust than type 1. It is therefore essential for heavier sailboats requiring greater mechanical force to ensure a firm rudder response in rough sea conditions.

This short-stroke version of the type 2 linear mechanical actuator offers a 300 mm stroke. This compact format is ideal for fitting in confined spaces under the deck.

The M81131 model operates exclusively with a 12V power supply voltage.

The cylinder is supplied with a complete assembly for the tiller shaft, including:

The tiller shaft (tiller pin)A cotter pinA top washer and a locking washerA 1/2 inch UNC Nylock nut

Alignment is critical. The pushrod of the cylinder must be precisely aligned with the rotation plane of the rudder stock. The maximum allowed tolerance is plus or minus 5 degrees to prevent any mechanical stress that could damage the system.

Yes, during installation, ensure the ram is mounted at a right angle (perpendicular) to the rudder stock arm when the tiller is perfectly centered (mid-travel position).

For a 12V installation with cable length up to 5 meters, Raymarine recommends using a 6 mm² (10 AWG) cable cross-section.

For a distance between 7 and 16 meters (including 10 meters), it is mandatory to use cables with a cross-section of 16 mm² (6 AWG) to avoid voltage drops.

No, it is strongly recommended to power the equipment via a separate battery from the engine starter battery. Starter transients can cause the voltage to drop below 10V, which would trigger a reset of the heading computer.

The actuator must be installed at least 1 meter away from any equipment or cables transmitting radio signals, such as a VHF. For SSB radios, this safety distance must be increased to 2 meters.

Yes, the power unit must be placed more than 2 meters away from the radar beam path. This beam typically extends 20 degrees above and below the antenna.

This type 2 mechanical ram is designed to work perfectly with Raymarine’s next-generation course computers (ACU series) as well as older SPX series models.

No, the M81131 reference is a model exclusively for 12V. If your boat is equipped with a 24V battery bank, you will need to choose the 24V version of this actuator (reference M81133).

Cutting and splicing the supplied cables is not recommended as it may compromise electromagnetic compatibility (EMC) performance. Always use the cables specified by Raymarine and adhere to the recommended cross-sections.

A voltage drop below 10V will not damage the equipment, but it may cause the heading computer to reset. This can result in the loss of some temporary data and alter the autopilot's operating mode.

To ensure optimal reliability, Raymarine recommends having the ram serviced every 2 years or every 1000 hours of use (whichever comes first) by an authorized technician.

The type 2 short mechanical linear actuator weighs approximately 8.24 kg (and just over 9 kg with full packaging).

Absolutely. The Type 2 ram exerts a very high force. If you are unsure whether your tiller arm or quadrant can handle this load, you must consult the manufacturer of your steering system.

Yes, if you are replacing an old short mechanical linear ram of Raymarine type 2, the center-to-center dimensions and the tiller pin mounting system are standardized to allow replacement without modifying your tiller quadrant.