Cal. 3186 was an automatic movement with date and independently-adjustable GMT hand. Introduced in 2005, it replaced Cal. 3185 in the Rolex GMT-Master II models until it was replaced by the updated Cal. 3285 in 2018. It was also used in the Explorer II from 2006 through 2011 until the larger Ref. 216570 was introduced with Cal. 3187.
- Rolex Explorer II (2007-2011), Ref. 16570
- Rolex GMT-Master II (2005-2019), Ref. 116710
Cal. 3185 used a simple ratchet on the hour wheel to advance the date. This was changed for the successor Cal. 3186, which has a click spring in its place. This change eliminated the characteristic “wobble” of the 24 hour hand when adjusting the time but has also proven to be less reliable. Cal. 3186 also features a Parachrom blue anti-magnetic hairspring in place of the Nivarox used on Cal. 3185.
The movement can be manually wound with the crown in position 1. Rotate the crown clockwise to wind the mainspring.
The date wheel is advanced along with the independent 12 hour hand, forward or backward, with the crown in second position (one notch out). Set the hour hand to the local time and date, leaving the 24 hour hand showing “home time”.
The time is set with the crown in third position (pulled all the way out). Rotate the crown clockwise to advance the minute and hour hands and counter-clockwise to turn them backward.