How to set time on a timex 1440 sports watch - Watches

SOURCE: timex 1440 sports digital watch time setting

1. Press and hold the mode button until it starts to blink, then release.
   
2. First the alarm time will come up.
   
3. Press the mode button once to get to the time and date.
   
4. The seconds will flash first. 
   
5. Press the st/stop button to toggle between the seconds, hour, minutes, date (month and day) and day of the week.
   
6. Press the lap/reset button to change the values.
   
7. When done, press the mode button again to return to normal.
   

SOURCE: need instructions for Timex 1440 Sport watch

http://assets.timex.com/instructions/w140Instr.pdf

SOURCE: How do i set the time on a timex 1440 sports

Here you go old chap:
http://assets.timex.com/manuals/

Cheers.

SOURCE: how do I change time on timex watch?

These are settings for the Timex SPORTS 1440 Magnetism (5b841 -W163US)
These are for the 4 button SPORTS 1440 (not 6 button) - they will also work for the 1440 SPORTS "Informer" model wrist watch - you will NOT find these instructions on the Timex website - only the 6 button which will not work on these watches is on that site!

TIME AND DATE

1. Press and hold MODE until HOURS digits flash (you'll be in Alarm Mode) Press MODE again to enter TIME mode, SECONDS digits will flash.
2. Press ADJUST to set SECONDS to zero.
3. Press START/STOP to select MINUTES.
4. Press ADJUST to change.
5. Repeat to set HOURS, MONTH, DAYS, and DAY of WEEK. Go through 12 hours to set AM or PM.
6. Press MODE when done.
7. To display DATE from Time display , press START/STOP.
8. With DATE displayed press and hold START/STOP, then press ADJUST to change display between DATE-MONTH and MONTH-DATE.
9. With TIME displayed, press and hold ADJUST, then press MODE to switch between 12-and 24-hour format.

1. Press and hold MODE until HOURS digits, DAY, and A or P (for AM or PM) flash.
2. Press ADJUST to change HOURS digits. Go through 12 hours for AM or PM.
3. Press START/STOP to select MINUTES.
4. Press ADJUST to change.. Press MODE when done.
5. Press and hold ADJUST, then press START/STOP to turn chime on/off. Press START/STOP again to turn alarm on /off. Release START/STOP when done.

1. Chronograph will count up to 24 hours. Lap times are not stored. After 40 minutes chrono display changes from seconds to minutes.
2. With time displayed, press MODE to select Chrono Mode.
3. Press START/STOP to start.
4. Press ADJUST to view lap time. Press again to sesume lap timing.
5. Press START/STOP to stop timing . Press ADJUST to reset chrono to zero.
6. Repeat for successive laps.

SOURCE: Timex Mid Size Sports 1440 WR50M

I came on here trying to find the same thing.  I accidentally got it back to 12 hour time by pressing the mode and lap/reset button at the same time when I was changing the time.  Hope it helps!