The vessel that would become Weazel was built by shipwrights James Taylor and John Randall of Rotherhithe, and was initially intended to be a private merchant craft.

The quarterdeck was lengthened from the original plans in order to incorporate a mizzen mast, with the intention that the additional sails would enhance speed and maneuverability compared to the traditional two-masted snow rig sloop.

[2] She was constructed with eighteen broadside gunports and two bow chasers, although in practice she carried only sixteen cannons with the remaining ports left unused.

She was formally commissioned on 24 June under Commander Thomas Craven, entering Royal Navy service at the height of the War of Austrian Succession which pitted coalitions broadly comprising France, Prussia and Spain, against Britain, the Habsburg monarchy and the Dutch Republic.

A contemporaneous newspaper report describes Weazel's crew as fighting "very bravely for a considerable time," before the advantage swung to the British with the arrival of the 58-gun fourth rate HMS Princess Louisa.

There she remained until 30 August when she was joined to a squadron under Admiral Peter Warren, with orders to reinforce a British fleet in position off the French island of Ushant.

[9] On the morning of 14 October the fleet was offshore from Cape Finisterre when it encountered a French force of eight ships of the line, escorting a convoy of 252 merchant vessels.

[11] Instead, Hawke made the signal for a general chase, freeing his captains from the constraints of a formal battle; the British then overhauled the French line and enveloped it from rear to van, capturing six ships.

Weazel had been too small to join the line of battle the previous day, but Admiral Hawke now deputised her to sail in haste for the Royal Navy's Jamaica Station with a message advising the likely course of the French convoy.