Autoprop Service and Repair Manuals

Autoprop propellers have been manufactured in 3 distinct styles of blade bearing construction. This page will help identify which model you have so the correct documentation can be downloaded.

Initially when first designed, Autoprop used a water lubricated bearing system. The thrust and upper bearings were made from loose balls on custom stainless steel races. This bearing style is therefore found in the oldest Autorops from the late 1990’s; it is still in use on the smaller Autoprops where commercial bearings are not available such as smaller H20 models. We refer to this style of bearing as Series I.

A redesign was needed for the Autoprop propeller once the power and hence the diameter of the Autoprops began increasing for larger sailboat applications. The redesigned bearing system used a high tensile steel blade nut encapsulated in grease using a watertight seal on the blade along with O-rings on all of the caps and fasteners. This style is Series II and was used from 2000 – 2006.

A subsequent redesign occurred and the bearing system was upgraded again to give the current Series III bearings.

Below you will find user manuals and service manuals for the Autoprop models. Series I and Series II typically had a single document, the latter Series III has a user guide and a bearing replacement guide. For all new Autoprops the Series III bearings (known as tab screw style) is used.

If there is any question about what bearing style or what Autoprop model you may have, please provide the Serial number of the propeller and we can advise accordingly.

Autoprop Bearing Types

Series I Autoprops are built around a water lubricated open ball bearing system. Each blade is open to the ocean with all of the components made from marine grade bronze or 316 stainless steel so the y do not corrode. The blades are locked in place using a special expanding blade cap to prevent the blades from becoming loose.

Series II Autoprops are designated by the propeller model prefixed with the bearing type (RB) and the locking style (TW).

For a 16.92″ diameter (430mm) H5 propeller the series I model would be H5-430-BB, where the 430 denotes the diameter (16.92 “) in millimeters.

Series II Autoprops are built around a grease lubricated roller bearing system. Each blade is sealed from the ocean using a main Lipp seal and several O-rings on the blade cap and grease ports. The blades are locked in place using a conventional tab washer and castellated nut to prevent the nut from becoming loose.

Series II Autoprops are designated by the propeller model prefixed with the bearing type (RB) and the locking style (TW).

For a 18.5″ diameter (470mm) H5 propeller the series II model would be H5-470-RB-TW, where the 470 denotes the diameter (18.5 “) in millimeters with a roller bearing and tab washer lock nut.

Series III Autoprops are also built around a grease lubricated roller bearing system. Each blade is sealed from the ocean using a main Lipp seal and several O-rings on the blade cap and grease ports like Series II. The blades are locked in place using a tab screw and castellated nut to prevent the nut from becoming loose. This tab screw is a custom bolt designed and manufactured by Bruntons Propellers that performs a similar role as a tab washer, but is considerably more robust and able to resist much larger forces.

Series III Autoprops are designated by the propeller model prefixed with the bearing type (RB) and the locking style (TS).

For a 19″ diameter (485mm) H5 propeller the series II model would be H5-485-RB-TS, where the 485 denotes the diameter (19 “) in millimeters with a roller bearing and tab screw locking bolt.

Yearly service for the current Series III style Autoprop (roller bearing, tab screw).