Here are some updates, guys ...
I have contacted the buyer
Kilowog and told him how to test the movement without any tools just to know, at the least, if it is in working condition or not .
Yesterday he proceded to TES 01 and it seemed to be OK.
Today is the day of TEST 02
Then will come the FINAL TEST, with very few chances to succeed IMHO
TEST 01 :
proceed without winding the wach
01 - pull the crown in 3rd position (hour setting position) and set the watch to 12:00 (AM)
02 - turn the rotating bezel until the 12 on the bezel is just in front of the GMT hand (without trying to move the GMT hand separately)
03 - crown still being in 3rd position, slowly turn the hands so that the watch shows 1:00 AM then check if the GMT hand is in front of the dot between the 12 and 13 on the bezel (the GMT hand should have move 15° clockwise)
04 - if everything's OK on step 3 set the watch to 2:00 AM and check if the GMT hand has turned 15° clockwise again and is in front of the 14 on the bezel
05 - if everything's OK on step 4 set your watch to 3:00 AM, then 4:00 AM, then 5:00 AM, etc ... checking every time if the GMT hand stays synchro
When the hour hand has moved 360° and the watch is set to 12:00 PM, the GMT hand should be just in front of the triangle (24) on the bezel
TEST 02 :
proceed only if TEST 01 went OK and start at a straight hour (12:00 AM, or 13:00 AM, etc ...)
01 - set the crown on 1st position (winding position)
02 - give the crown a few turns (5 to 10) so that the balance start to spin and the movement start working
03 - set you watch (12:00 AM or 13:00 AM , etc ...)
04 - screw the crowndown
05 - turn the bezel so that the printing showing the hour you have set is just in front of the GMT hand (so that the hour hand and GMT hand are synchro)
06 - block the bezel with a little piece of painter's tape (with caution) so that you're 100% certain that the bezel wont turn (just in case the bezel spring could be a little loose)
07 - put the watch on your wrist and live you life as you do every day ... move normally, speak normally, remove the watch before peeing and put it back after washing your hands, etc ...
08 - after a few hours, and repeteadly if needed, check both the hour and minute hands to know if the watch keeps good time (here we're not talking about seconds gained or loosed) and check the GMT hand to know if it stays synchro
09 - whhen you come to bed, late at night or not (not my concern), remove the watch from your wrist, put it in a safe place, dial up and leave it for the night
10 - when you wake, early in the morning or late in the afternoon (still not my concern) just check if the watch is still ticking, if it's still keeping good time and if the GMT hand is still synchro
FINAL TEST :
If everything went OK on TEST 01 and TEST 02 you can assert the movement is OK (but still a DG2813 and not a 2836)
Then you're ready for FINAL TEST which is to try to get a complete refund from the buyer, as he sold you a 2836 GMT movement and sent you a DG2813 movement, so he stoled you about $170 at the least (based on chazingtime prices : 328 - 158 = 170).
That final test will be the harder to perform as the seller is definitely a scammer and a profiteer, but you never know ... to gods of watches (
or some really beefy buddies) could decide to help you, visit the seller and frighten him to death enough so that he decides to send the money back then receive the watch back in return.