Skegness RNLI all-weather lifeboat Lincolnshire Poacher was called into action on Wednesday when a yacht requested assistance near the entrance to the river Steeping at Gibraltar Point.
The two-person crew of the 27ft yacht Morag were unable to start her engine to navigate the narrow channel into the river.
Skegness lifeboat launched at 4.45pm and located the yacht shortly after 5pm.
Lifeboat mechanic Mark Holley and crew member Lee St Quinton were transferred to the Morag in an attempt to fix the broken starter motor, while the tide rose enough to allow the lifeboat to tow her into the river.
At 6.30pm, having been unsuccessful starting the engine, a tow rope was attached to the yacht which was taken into the river.
The lifeboat returned to Skegness, reaching central beach at 8pm.