Airmar paddlewheel kit for DST800 and ST850 speed sensors

This is a spare part specifically designed by Airmar to replace the worn or damaged impeller in Airmar DST800 and ST850 speed sensors. It restores the speed measurement function of your sensor.

The paddlewheel is the rotating element of the sensor that measures the speed of water flowing under the boat's hull. Its rotation generates electrical pulses that are interpreted by the sensor's electronics to calculate speed and distance traveled.

The Airmar paddlewheel kit typically includes the paddlewheel itself, the paddlewheel shaft, and sometimes an O-ring or other small parts required for replacement. The main purpose is to provide the essential components for paddlewheel replacement.

A worn, fouled, or damaged paddlewheel can lead to inaccurate speed readings or no readings at all. Replacing it ensures your sensor delivers reliable, precise data—critical for navigation, performance, and fuel consumption.

Signs of a defective paddlewheel include erratic speed readings, zero speed while the boat is moving, or visible resistance when manually turning the paddlewheel. A visual inspection may also reveal broken or bent blades or significant buildup of algae and barnacles.

Yes, this kit is an authentic spare part manufactured by Airmar, ensuring compatibility and optimal performance with the DST800 and ST850 sensors from the same brand.

Airmar paddlewheel sensors are typically made from durable, marine-environment-resistant composite materials, such as high-quality plastics (e.g., reinforced nylon) designed to withstand saltwater, UV exposure, and abrasion.

On the contrary, replacing a worn paddlewheel with a new one restores the accuracy of your sensor. A properly functioning paddlewheel is crucial for obtaining reliable speed measurements.

Yes, as an Airmar OEM part designed for marine use, this kit is built with materials resistant to saltwater corrosion, ultraviolet (UV) rays, and marine environmental stresses.

Replacement frequency depends on boat usage, water conditions (presence of algae, debris) and regular maintenance. There is no fixed schedule, but it is recommended to inspect it regularly (at least once a year or during haul-out) and replace it at the first signs of wear or reduced performance.

This paddlewheel kit is specifically designed to be compatible with Airmar DST800 and ST850 speed sensors.

No, this kit is specifically designed for DST800 and ST850 models. Use with other Airmar sensor models is not guaranteed and may result in malfunction or physical incompatibility.

To ensure compatibility, check the model of your Airmar transducer. If your transducer is a DST800 or an ST850, then this kit is the correct replacement. The model name is usually engraved on the transducer body.

This kit is designed for DST800 and ST850 sensors. For older Airmar sensors, it is recommended to check the specific documentation for your model or contact a specialist to find the appropriate replacement part, as dimensions and mechanisms may differ.

No, this kit is a standard spare part for DST800 and ST850 sensors, regardless of the type of boat on which these sensors are installed. Compatibility is tied to the sensor model, not the type of vessel.

Replacing the impeller is a relatively simple maintenance operation that does not require advanced technical skills. It is generally considered a task that most boat owners can perform by following the instructions.

No, the Airmar DST800 and ST850 sensors are designed to allow replacement of the paddlewheel without hauling the boat out of the water. They feature a removable insert that can be extracted from inside the hull, with an integrated shut-off valve to minimize water ingress.

Generally, no specialized tools are required. You may need a screwdriver or wrench to remove the sensor insert retention cap, and possibly fine pliers to handle small parts like the impeller shaft.

In most cases, if the paddlewheel is replaced with an identical original part, a full recalibration of the sensor is not strictly necessary. However, it is always recommended to check the accuracy of speed readings after replacement and perform a recalibration if discrepancies are observed.

As a spare part and wear component, the warranty on the Airmar paddle wheel kit is generally limited. Wear parts are subject to specific conditions that may differ from those of main electronic products. It is designed to restore the functionality of an existing sensor.