PM Series: PM Task – Windlass Inspection & Service


The Windlass is an essential piece of safety equipment on a workboat or yacht.  When needed due to a loss of propulsion or steering control it must deploy quickly and safely to secure the vessel.  In addition to its safety purpose, cruising yachts rely on their windlass to anchor  in remote anchorages.  Failure to deploy or retrieve an anchor is at worse a safety hazard, and at best a major nuisance.  Often overlooked, periodic servicing is critical to the proper operation of the windlass.

Clutch Lever

Our example PM is based on a Maxwell windlass common on yachts.  Maxwell provides several variations of windlasses including vertical and horizontal chainwheel and capstan configurations, dual chainwheels, electric and hydraulic power, and optional band brakes.  While there are several variations, the basic operation and maintenance are similar.  Always refer to your owners manual for detailed operating and maintenance instructions.  WheelHouse users will find the owners manual in the Document Tab.

Most Maxwell windlasses use a hand clutch (using an inserted clutch lever) to engage/disengage the chainwheel from the capstan.  The clutch engages or disengages clutch cones which allow the  chainwheel and capstan to turn together or  independently.  These clutch cones and their riding surfaces require periodic service, including cleaning and greasing, to operate properly.

To service the above deck components, follow the detailed instructions in the owners manual to disassemble the topworks.  Clean all components and check for damage to springs, washers, plungers and other parts.  It is good to have the recommended spares on hand should any parts require replacement.  WheelHouse users will find the recommended parts in the Parts Tab.  Grease the clutch cones and the grease nipple (if fitted) at the deck plate using a good quality water proof grease.    Reassemble the topworks following the instructions in the manual.  Clean the chrome surfaces and spray with an anti-corrosion spray.

Upper Clutch Cone Removed

Upper Clutch Cone Removed

Lower Clutch Cone Removed

Below deck components include the gear box, worm drive, electric motor or hydraulic motor.  Inspect for corrosion, tightness (bolting, electric and hydraulic connections), leaks, and overall integrity.  Spray with anti-corrosion spray.

Gearboxes are either sealed and require no maintenance, or the gear oil may be changed every 3 to 5 years as required.  Use the oil recommended in the manual.  Some units may have a bank brake which requires periodic inspection including greasing the lead screw and inspecting the thickness of the brake lining.

Most windlass failures are the result of poor operating practices compounded by lack of maintenance.  We have seen fuse failures, bent deck bolting, motor failure, and damage to keys and internal parts when the windlass is used to “pull” a yacht to its anchor.  Failure to perform topworks servicing can result in seized clutch cones and drying out/failure of internal small parts.  Windlasses should be used to deploy and retrieve anchors from the bottom in a near vertical manner to prevent overloading the windlass motor or stressing the windlass mounts.  In addition, the windlass should be unloaded by securing the deployed chain using a bridle arrangement.

By following recommended operating practices and routine maintenance, your windlass will likely outlast your ownership, and will provide dependable service whenever you need it.

About our “Preventative Maintenance (PM) Series”

The PM Series addresses a PM found on most vessels by highlighting the requirements for a specific piece of equipment and then expand on equipment variations and techniques.  While you may not have the specific equipment referenced in the PM Series, the concepts should apply to your equipment.  The PM Series presents actual PMs taken from the WheelHouse Maintenance Management System.  WheelHouse users will always have the PMs and related documents and parts that are specific to their equipment.  Non WheelHouse users  should refer to their manufacturers guidance for your specific equipment when completing maintenance.  Contact WheelHouse for a product demonstration and pricing information.

Posted in Maintenance Log.