RWG Technical

A 7750 is a 7750 no matter who makes it...so yes, they all do this... For more insight into a 7750, have a look at these posts... 7750 how it works... 7750 Asian detailed review... There is much more in that subforum if you need more information... RG

More great insight. Good news is that the ETA balance wheel will fit on this model and correct the problem. Thanks for the update and research. RG

Have a look at this post, it should answer your question... Installing a Gen crown... RG

Very nice work, looks fantastic... RG

The top button moves a Cam inside the movement and you should hear and feel it clicking. The bottom button will also make a click sound when you reset the movement. RG

Great follow up information...thanks for the insight. RG

I am guessing that your model has the GMT hand closest to the dial face. I am trying to remember how it's done on that model (the GMT gear to movement connection), typically the GMT gear (or on the one I reviewed the Hour one) has notches in it (which act sort of like a clutch). It's doubtful that these notches would be slipping (you can feel how much tension is required to overcome the "clutch" as you change the GMT time when you set the hand), I would have to guess that your problem would be more related to the hand slipping on the post, than the GMT gear slipping...only a guess but seems more likely. There is little room on the 063 between the hands and dial, GMT hand getting out of sync with the rest is fairly common and whenever I have noted it, it was the hand hanging up on the dial face... RG

I have never seen any other models than the one I have shown here...seems as if yours is a much better made one without some of the flaws and defects this one has. RG

I have been using the term basterdized for these models since they first came out...they are not my favorite due to the mods... Not sure how long they will keep working, I really have a problem with the mods, and the way the gears are held in place...very poorly made... RG

Good idea to use the GMT as "Home" instead of GMT time, I would never have thought of using it to indicate anything but GMT time... It's always a compramise with these modified models, looks fine, but workings leaves something to be desired. The only GMT model I have is in my Genuine Glycine Airman 7, and I dont' wear it very often, as it's soooo friggen big.... RG

Congrats, enjoy your new toy... RG

My view, Use a 1.2 mm Black handle screwdriver. Crown in the Winding position, press on the release, and make sure the screwdriver bottoms out on the slot, press straight on the pin, when you can't feel anymore movement on the pin, gently pull the crown out...reinstalling gently insert the crown and stem, as you get close to the seating point where it locks in place as you push in, gently turn the crown CCW as your pushing...should slide in easily...no reason to touch the release pin on this model during installation. You should be able to knock the broken drill bit out of the case from the inner edge...I just broke 7 bits off in my own, (gold cobalt ones at that) and each time they came out no problem...gentle tap from the inside with a small punch I filled down to 1mm...you'll never get a 1.2mm drill in the pictured drill press... RG

Have a good trip, watch out for the Katoy's... RG

The NEW GMT Rollie with the Correct hand stack… This is the new version of the GMT model, it differs from the older version in a few area’s… 1. the hand stack is a-la Rolex, meaning the Hour hand is closest to the dial and the GMT hand is in between the hour and minute one 2. the movement is a 2836-2 (not even close to being designed as a GMT movement), which is poorly modified to try and sort-of-mimic-a-GMT movement, it fails on the functional side. 3. the Hour hand is Adjustable NOT the GMT one, this is an important point, as you will see later on. Now, if your planning on taking one of these watches apart, be warned, on each and everyone I have worked on, the GMT hand gear comes apart (the tube pulls out of the gear) and requires re-assembly…as you will see in the photo’s. Here is what happens when you take the GMT hand off, the post that is part of the GMT gear is SUPPOSED to stay attached to the GEAR, not come off with the hand… Have a look and see here… This is the movement, and next to it, is the GMT gear, and the GMT hand with the post still attached to it… So I take the post out of the GMT hand, carefully ‘cause if you loose it, your screwed big time…or if you bend the hand… Here is what we have to work with, small parts that have to be perfectly re-assembled (or they will jam up the gears) Reassembly is by using my jewel press to make sure the parts are exactly set at 90 degrees when they are put back together… GMT gear is re-installed on the movement and the rest of the parts are installed…as you can see, quality and parts usage leaves something to be desired…this is why I don’t like these bastardized movements, no parts, poor quality of the modifications, and hard to get working after overhaul…. In pieces after service… Overall view. IMPORTANT POINT This is not a GMT movement, it may look like a GMT, have the correct hand stack, but it doesn’t work like a GMT model… Why??? As with all our reps that take a movement designed to do one thing, and add new parts to make it work like something else (Daytona Running seconds at 6 for example), there are compromises. The extra gears that make this ETA 2836-2 into a GMT model means that although it looks like a GMT and the hour hand is independently adjustable, it wont’ work correctly if you independently change the hour hand. Mechanically the GMT gear is actually taking the place of the hour gear, with an added step down gear (to slow the GMT hand to half the hour hand speed, i.e. one GMT turn for each 2 turns of the hour hand). Here’s what I am trying to explain, but first lets back up a bit to assembling a Date movement, before we get into this model…it will be easier to follow. When you put the dial and hands on a Date movement (which the 2836-2 is), you need to do one important thing, that is to pull the crown to the 3rd position (the time setting one) and advance the crown (and therefore the time) until one thing happens: the date switches over… As soon as the date switches, it’s Midnight, and you don’t move the crown anymore. At midnight the hands (hour and minute) should be pointing at 12. So you install the hour hand pointing at 12. The next hand to install would be the GMT one. The GMT hand is independent and indicates…well GMT time….where it’s installed on the dial – does not matter except for one thing. That is that the GMT hand has to line up with a Marker on the dial. Which marker is irrelevant, as long as you line it up on one of the hour markers. In this example, I lined up and installed the GMT hand with the 9 marker. Since the GMT hand is independent of the Hour and Minute ones, and the GMT hand does one revolution every 24 hours, it’s installation criteria is only to line it up with one of the hour markers. After the GMT hand is on, I install the minute one, again lining it up with the 12 position like the hour one, after all it’s MIDNIGHT on the movement. Remember that as long as I don’t move the crown in the 3rd time setting position, it’s still midnight. So far so good…well that is until you start messing around with the hour hand…independently of the others (minute and GMT). You see on this watch, if you move the crown to the middle position (date change AND Hour hand position), you can turn the hour hand without affecting any other part of the movement… This is important to note, as I said earlier that only the 3rd position of the crown actually moved the date change time…so if that is true, then moving the hour hand – with the crown in the 2nd position – would…not affect the date change time. On any movement with a date, the only way the date change gear moves is by: 1. the watch running 2. you pull the crown to time setting position and advance the time. In the time setting position, all the gears on the top of the movement turn, cannon pin, hour wheel, GMT wheel, minute wheel, transfer gears, date change gears etc…. this only takes place in the time setting positon. So back to our modified movement. It stands to reason, that if the only time the date change gears move, is when your in the time setting position, then if you decide to move the Hour hand by itself in the second position of the crown, the date change gears are NOT going to move. As you see this dial here, it has just turned to 12pm midnight…the date switched over, I put the hands on and lined the hour and minute with the 12…the GMT is on 9 as that is a good position to install the hand and line it up with the dial markers…. If I push the crown in to the second position, and turn the HOUR hand alone, what time is it as far as the movement is concerned??? If you said anything but midnight, you didn’t follow along… As far as the movement and date change gears are concerned, nothing has changed, Midnight it is… As the hour hand moves along alone, the movement is not moving at all, it’s frozen at midnight… If you move the hour hand back by 3 hours to indicate 9PM on the dial face, the date will change over at – you guessed it – 9PM. I hope this is clear and easy to understand. If you want to use this watch as a GMT watch, then you can certainly set the Hour hand independently to wherever, as long as you don’t care when the Date changes over…every hour off of “Midnight” you move the hour hand, is an hour away from “Midnight” that the date is going to switch over…it’s designed this way…I don’t build them, only try and fix them… This is probably the reason ETA GMT movements have the GMT hand move independently in the second crown position…that way the date change time stays at Midnight. Not sure on the Genuine Rolex and how it works, but I suspect they have designed it to work the right way as a true GMT model, and retain the midnight date change with the Hour hand independently adjustable, or maybe not, I don’t really know… As with all these reps, they may LOOK like the real deal, hand stack and all, but for $200, and a Basterdized 2836-2 QUAZI GMT movement put together with case clamps and some new gears, it’s not going to work like the real watch costing $5000 or more…it can’t… expecting it to do otherwise is unrealistic. Thanks for reading, RG

You need a small drift (or punch) that is about 1.00mm in diameter... drive the broken drill bit out from the inside of the lug towards the outside. RG

Great idea. Wonder how many sellers there are of the 47mm spring bars...bet those are hard to find. I fill the hole with a structural epoxy, and sometimes it can form some new threads...but in any case, it will hold the bars in place, that is unless your replacing the strap all the time. RG

The gap between the datewheel and the movement is about the same...until they design a true 7753 copy, with the datewheel ABOVE the transfer gears, were stuck with the gap... RG

I think once cleaned and oiled, it's about a 8 out of 10, the ETA being a 10. Not sure if any or all of the ETA parts will fit, I do know the cannon pin from an ETA does fit, as this one was really bad, and I could not fix it...that is the first bad cannon pin on this new model. The older Asian 7750, all the cannon pins are crap, but the ETA part does not fit on the old ones... RG

Well that sheds a different light on the question... I use about 1 full yellow oiler of 8217 on the barrel sides, then install the mainspring, then use 4 yellow oilers of 8141 on the mainspring itself, then after assembly, a full black oiler of D5 on the pivots for the arbour. Works for me, quantities of course vary by the movement type and size... RG

I was not aware of this, as far as I know, the only ETA 7753 (Valjoux is long gone) datewheels Mark has, are those that I removed or he removed from the customers watches...he does not have any spare wheels... Only a few ETA parts will fit the Asian movements, the datewheel is one of them... Yes and no, technically a ETA 7753, or 7765 or any of the other versions is a 7750, but as on the ETA, if you remove the transfer gears on the Asian one, it's not a 7750 until you put in some new parts, because the 30 minute gear is modified to accept a transfer gear, not a subdial hand... If you look at the ETA tech sheets for the 7750 series, most verisons use 7750 parts. On this new Asian model, there are some new parts, that are only usable for the 7753 layout. The new bridge on the dial side is custom made and designed to work as a 7753 with the transfer gears jewels built into the actual plate, and not an add on... It started out as a 7750, but removing the transfer gears alone, will not make it into a 7750 again, some new parts would be needed... In any event, it's a big improvement over what we had 2 years ago, whatever we call it won't change the fact, it's here to stay, and the Chinese (or whoever is making these) are either reading these posts, or listening to someone, as they are improving the movements all the time, and to me, that is great news...if they could only go easy on the oiling of the mainspring...or even better, oil the movement before sending it out... RG

Oiling a watch is a huge topic on it's own...too tedious to try and cover in a post... The barrel sides are coated with a special grease, the mainspring in installed, then oil is applied to the spring coils, and once the cover is installed, a different oil is applied to the arbour pivots...3 types on this one part alone, in varying quantities... Best to get some oiling charts from ETA.www.eta.ch, and have a look. It's more than I am willing or able to explain, sorry. There is probably information on Time Zone on oiling a watch... RG

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Good valid points... I don't think there is any way we can control the amount of scammers on the bay, they will find a way somehow... The general rule of thumb for parts interchangeability is that Asian and Swiss parts do not interchange. As for the 7753 datewheels, as far as I know, I am the only one that has been able to source ETA 7753 Datewheels, so far I have gotten 6 or so... The biggest issue with any of these movements, is the fact that this one is not a 7750, but continues to be called this by the sellers...which only confuses everyone... How about Asian 7750 (with 7753 subdials) that way it's clear to everyone. It would be nice if there was a numbering system we could use to make it clear to everyone what they have in their watch...especially when you see a post "I have a 7750 in my XXX, can I install a ETA 7750 as a direct fit... And lets not forget, the differences in the hand sizes, subdial locations (Post 2000 Daytona) etc...very confusing for sure...especially when they are all called Asain 7750... RG

I did not note anything on the backside of the movement that indicated that this was a newer modified version. It looked the same as they all do from the rotor side... I think this is a fairly new watch, so maybe this is the latest version in those coming out of the factories...lets hope so... There is nothing inherently wrong with the other versions of this new Asian 7753 layout model, but this design (as you can see in the pictures, and if you compare to the other ones I have posted about) is a much improved design in many area's of the datewheel retention, and 30 minute transfer gears. I think we should refer to these as "Asian 7753 copies" as that most accuratly describes the subdials, especially if someone is considering upgrading...a ETA 7750 is not a direct replacement for this model... RG RG

Exactly my point, it's got a 7753 dial layout, not a 7750... Dealers are still using the terms "Unitas" and "Lemanina", so I doubt we will ever be able to change any of this...but for those thinking of upgrading, they are mislead when the buy a ETA 7750 and find out the subdials are not the same as on their rep... It's a quasi 7753, more so than it's a 7750... RG