A boat trailer winch is a device used to load a boat onto a trailer. Consisting of a cranking mechanism, a spool of cable and a hook, the boat trailer winch is attached to a steel ring on the bow of a boat. As the cable is cranked back onto the spool, the boat is pulled onto the trailer. There are two basic designs of boat trailer winch: a manual type that incorporates a hand-cranked winch to spool the cable, and an electric model that uses an electric motor to crank the cable onto the spool.
The boat trailer winch is not designed to operate as a tie-down component, however, many boat owners commonly use it in that manner. The locking mechanism in the boat trailer winch is not designed to withstand serious jolts, such as those encountered when pulling a trailered boat on a highway. The boat trailer is often fitted with a small length of chain and a snap-hook on the same part of the trailer as the winch. Once the boat is winched onto the trailer, the snap-hook is attached to the ring beside the boat trailer winch hook and serves to secure the boat to the trailer.
It is not uncommon for a boat trailer winch to use a nylon strap in place of a steel wire cable. The flat strap is common on both the manual and electric winch and is typically easier to use than a wire cable. When a wire cable is wound tight, it often digs into the layers of wound cable, creating pinch spots. These spots can make unspooling the cable very difficult as well as create weak spots in the cable by breaking strands of wire inside of the cable. The flat nylon strap remains tightly wound and does not bind or pinch itself when wound tightly onto the winch spool.
Electric or power winches commonly require a battery to be mounted on the tongue of the trailer to provide power for the winch. It is generally recommended that a deep cycle, marine-type battery be used for this application due to the prolonged cranking power the battery can provide to the boat trailer winch. Placing a trickle charger on the battery when the boat is not in use is the preferred method of maintaining a proper level of charge. It is also recommended that a small amount of marine-quality grease be placed on the locking mechanism of a manual boat trailer winch to keep it operating smoothly.