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Eta 7750 Service Walkthrough - The Industry Standard Chronograph

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ETA 7750 Service Walkthrough



The 7750 was first available in 1974, having been one of the first movements to be designed with the aid of a computer.  It's hard to believe that the 7750 is still the industry standard movement for chronographs considering it's history.


It was developed over 40 years ago by Valjoux, who was then a legendary movement maker that was part of the giant ASUAG conglomerate.  But by the end of 1975 production was stopped due to the onslaught of the Quartz Era, and the 7750, along with many other mechanical calibers, was abandoned.  Industry demand for this movement was so low that the stock produced in that 1 year manufacturing lasted until 1982!  Such was the devastation of cheap Japanese produced quartz watches to Swiss manufactures.


History may have forgotten the 7750 except for the local management at Zenith who ignored the orders by Valjoux to destroy the dies and equipment used to manufacture the 7750, instead hiding the equipment away from corporate eyes.


You can find many more fascinating facts about this caliber online, and it's well worth the read.




This walkthrough will be very detailed, and I hope this will give people the courage to tackle this movement.  I've serviced quite a few calibers, and this is one of the most beautiful, with a very logical layout. 


ETA7750 Tech.PDF


If you have built your skills with basic movements, and become proficient in servicing them, I would highly recommend this movement to be your first chronograph to tackle.




Lets begin.




Remove the Day Indicator and store it in a safe place where it won't be damaged.




Unscrew (0.8 Driver) the Jumper Maintaining Plate and remove it.





Do the same for the Date Indicator Maintaining Plate





Carefully remove the Jumpers Spring, holding it with a piece of pegwood so it doesn't ping away.




Next remove the jumpers for the day and date.





The jumpers differ from one another, so here is a reference photo so you can see the difference.




Remove the Date Indicator and place it in a safe place where it won't be damaged.




The last piece to remove on the Date Platform is the Double Corrector




Now unscrew (1.4 Driver) the Date Platform and gentle pry it from the movement.





Be careful when removing this plate, as there is a fine spring pressed into the plate that can be easily damaged.





Here is a reference photo of the screws that hold the Date Platform.




Remove the Hour Hammer Spring, once again using the pegwood to hold the spring while removing the tension.




Here is a reference photo of the correct orientation of the spring.




Remove the Hour Counter Lock.




Remove the Hour Hammer Operating Lever.




Next is the Hour Hammer, be careful when removing this item so as not to damage the Hour-Counting Wheel.




Now remove the Hour-Counting Wheel.




Remove the Date Indicator Driving Wheel




Remove the Day Star Driving Wheel




Then remove the Intermediate Calendar Driving Wheel




Remove the Hour Wheel




Then the Minute Wheel




Remove the Cannon Pinion, which does not require a puller.




The last component to be removed on this side of the Main Plate is the Driver Cannon Pinion.




To lift the Driver Cannon Pinion I used what Mark used, a set of hand lifter from Horotec (MSA05.007); but

you can also use a Presto Tool (30636-1) which will also work well.




The dial side of the movement is now complete disassembled.

Flip the movement over and unscrew (1.5 Driver) the Oscillating Weight.





To remove the Hammer Spring lift it up gently over the automatic work and move it inwards.

This will move the tail of the spring in a clockwise motion to the opening in the slots, which will free the spring.




Slide out the Clutch Spring.




Here is a reference photo of this spring, and it's orientation.




Remove the screws (1.4 Driver) for the Automatic Device Bridge, and gently pry it loose.





Here is a reference photo of these screws for the bridge.




Once the Automatic Bridge has been removed, the two wheels for the automatic work are able to be removed.

Below is a reference photo of how the sit inside the bridge.




We now begin to disassemble the chronograph section of this movement.

Begin with removing the Hammer, 2 Functions.




Next remove the Clutch 60s, 2 Functions.




Then remove the Minute-counting Wheel, 30min.




Remove the Chronograph Wheel 60s, 30min.




Gently lift out the Oscillating Pinion, 60s.




Here is a reference photo of the orientation of this pinion.




Unscrew (1.4 Driver) the Chronograph Bridge and gently pry it off the Train Wheel Bridge.





Remove the Ratchet Driving Wheel.




Remove the Chronograph Wheel Fiction.




Unscrew (1.4 Driver) the Operating Lever, 2 Functions.





Unscrew (1.4 Driver) the Lock, 2 Functions.





Next remove the Minute-counter Driving Wheel, 30min.




Slide out the Operating Lever Spring, 2 Functions.




This spring can be fitting in both directions; but only 1 way is correct.

Here is a reference photo of it's correct orientation.




Remove the Switch.




Here I digress from the order the SwissLab document illustrates the order of removal.

They show to remove the Chronograph Cam before removing the Hammer Cam Jumper.

This in my opinion is not the best way, as all the force from the jumper is pressing on the cam whilst your trying to remove it, and could lead to damage.

Instead I move the Chronograph Cam until it reaches the notch as shown in the photo below.




Then lift the Hammer Cam Jumper up to the top of the Chronograph Cam, which will release it's tension.

Then, just as you removed the previous hammer, rotate the jumper to the opening in the slots, which will free the spring.




Now you can unscrew (1.4 Driver) and remove the Chronograph Cam safely without tension on it.









Once the tension has been released, unscrew (1.4 Driver) and remove the Balance Cock.





Then unscrew (1.4 Driver) the Pallet Bridge and remove the bridge and Pallets.






Unscrew (1.2 Driver) and remove the Ratchet Wheel.





Then remove the Crown Wheel.






Unscrew (1.4 Driver) the Train Wheel Bridge and gently pry it off the Main Plate.





Note that one of the screws is under the Operating Lever.  This needs to be moved out of the way to access this screw.




The last level of this movement contains the train.

Here is a reference photo of the wheel locations.




Remove the Stop Lever.




Remove the Great Wheel.




Here is a reference photo of the underneath of this wheel.




Remove the Third Wheel.




Here is a reference photo of the underneath of this wheel.




Remove the Second Wheel.




Here is a reference photo of the underneath of this wheel.

Note this has the long lower pivot.




Remove the Escape Wheel.




Here is a reference photo of the underneath of this wheel.




Then remove the Barrel.




This completes the removal of the train.

Flip the movement over so we can complete the disassembly by removing the keyless work.




Firstly, release the tension from the Setting Lever Jumper.




Then unscrew (1.2 Driver) and remove the Setting Lever Jumper.





These are unique screws with pointed ends, and below is a reference photo of them.




This will also remove the Intermediate Setting Wheel.




Next remove the Setting Wheel




Then remove the Yoke.




Remove the Setting Lever.




Remove the Rocking Bar.




Now pull out the Stem.




Once the Stem is removed the Winding and Sliding Pinion should fall out of the movement onto your work mat.




Disassembly of the 7750 is now complete




If you've come this far, congratulation on completing the disassembly.

Make sure you pegwood all the jewels and reinstall the Balance back onto the movement for cleaning.




Assembly of the movement will be posted as soon as I complete the write-up.


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Excellent walkthrough again Lawson. I am interested in your assembly as there are a few sequences that can be adopted. i.e. I could not get the clutch spring fitted using the Eta assembly sequence I found fitting the spring before the bridge far easier.

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What a sterling job Lawson. You've just set the bar that walkthroughs so will be compared with in the future. :)

You should start producing "Haynes" type manuals for horologists, they would be best sellers!

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Thanks for the positive feedback guys.  Editing the photos and writing up the walkthrough is far more difficult then the service on this movement. :p


I had to rebuild the software from scratch on a friends PC today, so that put me a little behind in this service, but I'm back into it now.

Parts are in the cleaning machine as I type this up, so the assembly and write-up shouldn't be far off, Lord willing.

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Thanks mate :)

But all praise goes to my Lord and Saviour, Jesus Christ, for giving me the gift of being able to do this work and write-ups for you guys.

My hope is that they inspire others to "give it a go" like I did 11 months ago, and not be fearful of a challenge.


The reward that comes from succeeding and seeing a movement come to life are hard to put into words.

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The movement service is complete, and I'm doing the write-up now.


But just as a teaser, here's how the movement looks on the Timegrapher straight after I'd finished the service .... totally UNADJUSTED :)




I'll adjust the timing to COSC standards another day ... I wanna get the assembly write-up posted tonight if possible.



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Awesome work. I just bought a 7750 and will start disassembly soon. Your walk of the disassembly is a great help. I can't thank you enough. I can't wait to see the rest.

Thanks again.

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Awesomeness in all splendor for a walkthrough! Very nice job and much raising the bar for walkthroughs! Very solid and desired movement to know in depth...great choice!


Thank you Lawson for putting the time into this!





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Thanks guys for all the positive feedback on this walkthrough.

Please feel free to post negative feedback, I'm here to learn as well, and welcome negative constructive comments from those who have years of experience with this movement.


I must apologies for the delay on posting the assembly, but I didn't realize just how long it would take to create all the pictures and do the write-up.



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ETA 7750 Walkthrough

Part 2




Now we come to assemble the movement.

Here are the lubricants that will be used.




Now nothing creates more discussion and controversy than which lubricants should be used on movements in various applications.

This is how I approach it ... your choices may vary.


The 7750 I am servicing here is a "Top Grade" ETA movement made for TAG, which would normally be cased with a display back.

Because of this I will be using Molykote DX instead of Jismaa 125 or 9501 grease for areas that will be seen.  As their lubricating qualities are very close, my choice of using Molykote DX is purely for ascetic reasons, as its less visible to the eye, then the bright colours of the 9501 and Jismaa 125.  You will notice that Molykote DX is recommended in the 7750 PDF; yet on the SwissLab documentation it states to use Jismaa 125, so all these lubricates are recommended and safe to use.


If this was a "Standard" or "Elabore" Grade movement with a full metal caseback, then I'd just go with the SwissLab recommendations, or 9501 for ease of servicing.


With all that being said, here is the Lubrication Index for this walkthrough.





  • Make sure your work area has been wiped down to remove any dust, and clear away any unneeded items from around your workspace.
  • Inspect your Screwdrivers and Tweezers, and dress them up if needed.  There is nothing worse than marring a screwhead, or have components ping from your tweezers because they need to be re-dressed.
  • Put on some finger cots, or latex gloves.  Personally, I use only one latex glove on my left hand, as any manipulation with my right hand will be done with my old trusty customized Dumont Brass #4 tweezers. NEVER touch cleaned parts with bare hands, this will leave prints and tarnish the finish over time.

We begin with the parts fresh from cleaning.

Try and arrange them in a logical order to start with, this will save you time fishing for parts later on.




The 7750 has 7 types of screws, and you'll need 4 sizes of screwdrivers - 0.8, 1.2, 1.4, 1.5mm

1) Date Platform, Crown and Ratchet Wheel Screws

2) Setting Lever Spring Screws (Note the pointed ends)

3) Hammer and Cam Screws

4) Oscillating Weight Screw (Single Screw with the short thread)

5) Pallet Fork, Main Plate, Chronograph Plate, Automatic Work Plate Screws

6) Screws for the Jumper Maintaining Plates

7) Single longer screw for the Balance Cock


I like to arrange all the screws in groups like this, that way they are quick to find, and mismatching screws can't happen.




One more thing to note on this assembly walkthrough, is that I started by using the 7750 plastic movement holder.

I quickly however changed to a Bergeon 4040 movement holder, and found this much better when it came time to fit the plates and align pivots to their jewels.

I'd suggest you use the Bergeon 4040 holder right from the get go.


Lets begin!


Place the Barrel on the Main Plate




Next is the Escape Wheel




Followed by the Second Wheel, which has the long pivot for the sub-dial hand.




The Third Wheel is next to be installed




With the last wheel in the train being the Great Wheel.




Place 2 small spots of D5 as shown, so the Stop Lever will have a smooth action.




Install the Stop Lever.




Now install the Barrel/Train Bridge. (1.4 Driver)

Make sure all pivots are located correctly and the train is free spinning BEFORE tightening down.

Once tightened down check end shake.




Install the Crown Wheel




Then the Crown Wheel Core and screw down (1.2 Driver).




Install the Ratchet Wheel and screw down (1.2 Driver).




Once this is done, using a 1.2 Driver, turn the screw on the Ratchet Wheel a 1/4 of a turn to add energy to the Mainspring, and check the free running of the train.






Next is the keyless work.


Lubricate the Winding and Sliding Pinion as shown below.

Also add a spot of 9501 to the Main Plate where the Winding Pinion will come in contact.




Be sure when installing he Sliding Pinion that it's seated properly on the Stop Lever




Install the Sliding Pinion




Install the Winding Pinion




Lubricate and install the Stem.





Next is the Driver Cannon Pinion.

This is one area that needs a lot of lubrication, as it will bind and damage the movement if it becomes dry.




To install the Driver Cannon Pinion I use a Horotec Hand Fitting Tool MSA 05.011




Once properly lubricated, install the Driver Cannon Pinion




Before installing the Rocking Bar, lubricate the points on the spring.




Install the Rocking Bar.




Install the Setting Lever




Install the Yoke.




Place the Setting Wheel on it's post.




Construct the Setting Lever Jumper with the Intermediate Wheel




As noted above, the screws for the Setting Lever Jumper are the ones with the pointy threaded ends.




Be sure to lubricate position points on the setting bar before you lever it into place.




Install the Setting Lever Jumper / Intermediate Setting Wheel.




The keyless work is now complete, check it is functioning correctly, then turn the movement over.






Once the movement is turned over install the Pallet Fork.




Then install the Pallet Bridge.

Once the bridge is in place, give the mainspring a few winds and check the free movement of the Pallet BEFORE

screwing it down (1.4 Driver)

After tightening down check the end shake.

Use 9415 on the Exit Pallet Stone to lubricate the escapement.




Replacing the Balance and oiling the Incabloc Jewels is next.

Place the Balance back onto the movement, checking that it's free running before tightening the screw (1.4 Driver).

Once tightened check side shake and end shake is correct.




Remove the Incabloc Jewel, and then remove the Balance.

Note the longer screw that is used to secure the Balance Cock.




Cleaning them carefully by soaking in a container with Lighter Fluid ... I use Zippo Fluid.




Once clean, dry the Balance and Incabloc Jewel and place a drop of 9010 on the Jewel as shown below.

Make sure it covers at least 1/3 to 1/2 of the jewel, without the oil touching the sides of the jewel.




Give the movement several winds to add some power to the Mainspring.

Replace the Balance back on the movement and refit the Incabloc Jewel.

Check that the Balance is oscillating freely.




Then repeat the process for the jewel only on the Main Plate.




Next to be installed is the Hammer Cam Jumper. Here is my method for installation.

Place the Hammer Cam Jumper into position, turning it clockwise to lock it into the slots.

Then place the Chronograph Cam on it's post, so that it rests on top of the cam jumper ... as shown below.




Then while holding the arm of the cam jumper back, seat the Chronograph Cam into position and affix the screw (1.4 Driver)




Install the Switch




Insert the Operating Lever Spring, 2 Functions.

Make special note of the orientation of this spring, as it will fit in both directions; but only one way is correct.




Without lubricating, install the Minute-counter Driving Wheel, 30min.




Install the Lock, 2 Functions, and screw down (1.4 Driver)




Before installing the next item, which is the Operating Lever, 2 Functions, be sure to lubricate the hinging point from underneath with D5.




Then install the Operating Lever, 2 Functions.

Be sure that the spring arm of the Lock is out from under the Operating Lever and screw down (1.4 Driver).

Place D5 into the little slot opening in the top of the hinge point.




Install the Chronograph Wheel Friction.




Install the Ratchet Wheel Driving Wheel




Before placing the Chronograph Bridge onto the movement, you need to oil the jewel circled in the image below with D5




After oiling that jewel install the Chronograph Bridge.




Next, place the Reduction Wheel into the hole in the Chronograph Bridge.

Note that there is no post to locate this wheel, as it's on Automatic Device Bridge which will be installed later.




The next item is the Oscillating Pinion which seems to cause people a lot of frustration.

Here's my method to install it.

Firstly, be sure of the correct orientation, as shown below.




Pull the Crown out to the third position to engage the Stop Lever and hack the movement.

Keep the movement in this hacked position until the Automatic Device Bridge is installed.

Then install the Oscillating Pinion and seat it into it's lower jewel. 

You'll know you've done this correctly when it sits up straight and centered in the slot ... as shown in the image below.

By taking your time and getting it well seated you will have less trouble when installing the Clutch later on.




However, before we install the Clutch and Automatic Device Bridge, there are a few wheels and a hammer that need to be installed.

Install the Chronograph Wheel, 60s, 30min




Install the Minute-counting Wheel, 30 min.




Install the Clutch 60s, 2 Functions.

The Clutch needs to slip underneath a small click spring for the Reversing Wheel, so be careful not to bend and damage this spring.

Then gently lift the arm of the Clutch over the Oscillating Pinion. 

Yes, it's a delicate job, but with a steady hand, patience and well dressed tweezers, it's not too hard.




Before we install the Reversing Wheel, we need to lubricate it.

The product needed is Lubeta V105, which is an immersion, or dip, lubricant.




Simply hold the Reversing Wheel with tweezers and dip it into the solution.

Then allow it to dry, which takes about 10 minutes.

This leaves behind a waxy type lubricant that has impregnated deep into the wheel.




Once dry, install the Reversing Wheel




Install the Hammer, 2 Functions.

Make special note of the orientation of the cam to the hammer.

You may need to rotate the cam into this position before you fit the hammer.




Now it's time to install the Automatic Device Bridge.

Make sure all wheel pivots are correctly located in their jewels before tightening down (1.4 Driver)

Pay close attention that the Oscillating Pinion is still seated correctly in it's pivot hole on the Clutch.




One other troublesome operation for people is installing the Clutch Spring.

This is my method of installation.


Slide the long arm of the spring into it's position until the shorter end is touching the automatic bridge.

Then with your tweezers grab the point illustrated below and lift it over the locating screw.




Once over the screw, push it forward and until the loop is seated on the locating screw.




Lastly, install the Hammer Spring, 2 Functions.




Now you can un-hack the movement by pushing the Crown into it's winding position.

Check that the Oscillating Pinion is being driven by the movement.

Check the Chronograph functions are engaging and dis-engaging correctly by operating the pushers.


Once you are satisfied all is well, turn the movement over.






Now we come to the calendar work.




For this I place the movement back in the Horotec 7750 plastic holder (MSA 09.050-01)




Install the Free Cannon Pinion




Install the Minute Wheel.




Install the Hour Wheel




Install the Intermediate Calendar Driving Wheel




Next the Day Star Driving Wheel

It is most important that you line up the driving tooth of this wheel with the marker on the Main Plate.

If the wheel appears to be half a tooth off proper alignment, bring the Crown out to the hand setting position and adjust so the tooth lines up perfectly.

Failure to do this will result in improper synchronization of the day and date.




Install the Date Indicator Driving Wheel.

This time you line up the wheel's driving tooth with the post for the Intermediate Calendar Driving Wheel.

Failure to do this will result in improper synchronization of the day and date.




Install the Hour-counting Wheel




Install the Hour Hammer




Install the Hour Hammer Operating Lever




Install the Hour Counter Lock




Install the Hour Hammer Spring




Place on the Date Platform, and secure down (1.2 Driver)




Install the Double Corrector, making sure the spring is correctly positioned.




Place on the Date Indicator.




Install the Date Jumper.

Be sure you have selected the correct jumper, as the Day and Date Jumper are not Identical.





Install the Day Jumper




Install the Jumper Spring.




Place on the Date Indicator Maintaining Plate and screw down (0.8 Driver)




Place on the Date Jumper Maintaining Plate and screw down (0.8 Driver)




Fit the Day Indicator, and test the function and timing of the Day/Date




Turn over the movement to fit the last item.






The last item to fit is the Oscillating Weight.

Gently place it on the movement, check it's meshed properly and then screw down (1.5 Driver)




Service on the ETA 7750 is now complete, and adjusting the timing of the movement is the only operation left.


I hope this has been of interest and helps those wishing to tackle this caliber.  I'm sure, as I did, that you'll find it a fun and reward movement to service.



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Astounding work and presentation Lawson. Having done a couple of small walkthroughs, I can really appreciate the time and effort that has gone into this. Thanks buddy!

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Hi Lawson,


I have no words to praise enough this excellent job and documentation! You have excelled yourself in this incredible work of love. Much appreciated your sharing and time put into it!


My friend, you ask about negative feedback, well I have one: you are too far from my house and I'd love to be your neighbour! :)





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      Here is a reference photo of the Circuit and screw.

      Next remove the Coil by lifting it with the end with no circuit tracks on it, as shown below.

      Now unscrew the 2 screws, using a 1.2mm Screwdriver, that holds the Train Bridge and lift it off gently.

      Here is a reference photo of the Train Bridge and screws.

      Next remove the wheels of the train carefully, then the Rotor and Stator.

      From left to right there names are: Third Wheel, Second Wheel, and Intermediate Wheel.

      And here are the Rotor and Stator.

      Unscrew the single screw, using a 1.2mm Screwdriver, that holds the Centre Bridge and remove it.
      The Cannon Pinion should be on the centre post of the bridge and come away with it.
      NOTE: This screw is also unique with a thicker head, remember it's location.

      Here is a reference photo of the Centre Bridge, Cannon Pinion and screw.

      Next remove the screw, using a 1.2mm Screwdriver, that holds the Plastic Setting Lever Cover, and remove it.

      Here is a reference photo of the Setting Lever Cover and screw.

      Then lift out the Setting Lever and Primary Yoke.

      Lastly, pull out the Stem and the Sliding Pinion should fall to your work mat.

      You have now completely disassembled the movement ... WELL DONE!! :)

      The black plastic outer ring can not be removed, it is riveted to the Main Plate

      All the parts can be put in the cleaning machine or Ultrasonic ... EXPECT THE FOLLOWING PARTS!
      Battery Circuit Coil Rotor  

      I hope this was a fun movement to begin your journey into watch repairing, and that it builds your confidence to advance further.

      Assembly will be posted soon...stay tuned!
    • By Lawson
      ETA 251.626 Service Walkthrough
      The 251.626 is often found in mid to high-end quartz chronographs on the market today.
      ETA 251.262.pdf

      It is a fairly complex quartz movement that has 5 motors, 2 with Red Coils, and 3 with Green Coils.

      To begin the service we start by removing the 3 Indicator Maintaining Small Plates, and Date Indicator.
      A 1.4mm screwdriver is all the is needed for every screw on the movement.

      Here's a reference photo of the 3 screws for the Indicator Maintaining Small Plates.

      There are no more components to remove from the dial side of the movement.

      Once the movement is turned over, remove the 2 screws that hold the Magnetic Screen.
      Once the Magnetic Screen is removed all the coils are very exposed, so work around these coils with great care.

      Here's a reference photo of the 2 screws for the Magnetic Screen.

      Next unscrew the 6 screws holding the Additional Printed Circuit and gently lift it off the movement.
      Store the Additional Printed Circuit away separately and safe from the rest of the parts.

      Here's a reference photo of the 6 screws for the Additional Printed Circuit.

      Next we tackle the 2 trains with the red coils.
      Right Side - Minute Counter
      Left Side - Hour Counter

      The right and left trains contain different size wheels and should be kept separate for ease of assembly.
      We shall start with the right side.
      Remove the Minute Counter Bridge

      Next remove the Gear Train and the Rotor.

      Next remove the Coil and Stator.
      Store the Coil away separately and safe from the rest of the parts.

      Here's a reference photo of the components and their corosponding screws.
      Note the 4 spokes on the Minute Counting Wheel.

      Remove the Hour Counter Bridge.

      Remove the Gear Train and the Rotor.

      Remove the Coil and Stator.
      Store the Coil away separately and safe from the rest of the parts.


      Here's a reference photo of the components.
      Note the 3 spokes on the Hour Counting Wheel.

      Store these 2 trains in separate sections in your parts tray, and when cleaning store them in sparate parts containers.

      Next remove the Chronograph Bridge

      Now remove the Chronograph Wheel

      Unscrew the Green Coils and remove them.
      Store the Coils away separately and safe from the rest of the parts.

      Here's a reference photo of the components and their corresponding screws.

      Remove the Train Wheel Bridge.

      Remove the Wheels of the Train.

      This is quite a complex train of wheels.
      So to assist you I've cleaned up the rather cluttered schematic supplied by ETA and colour coded each wheel and it's location on the Main Plate.

      Here's a reference photo of the top of the wheels, also colour coded to assist you.

      And also the underneath of the wheels, also colour coded to assist you.

      Remove the Rotors and Stators.

      Unscrew the 3 screws that hold the Upper Plate and remove it.

      Here's a reference photo of the Upper Plate, Connector, and the corosponding screws.

      This now exposes the Electronic Module.

      Remove the Stop Lever/Switch

      Remove the Cannon Pinion with Driver.

      Then remove the Electronic Module.

      Pull out the Stem and Sliding Pinion.
      Now store the Electronic Module away separately and safe from the rest of the parts.

      Remove the Minute Wheel, the Hour Wheel, and Contact Intermediate Wheel.

      Before we can remove the Date Indicator Driving Wheel, we need to pull back the Date Jumper.
      Gently lift the tab (Yellow Arrow) until it's at plate level and pull it backwards.
      This will pull the arm of the Date Jumper back and allow you to remove the wheel.

      Here's a reference photo of the wheels.

      Lastly we need to remove the keyless work.
      Unscrew the Setting Lever Spring and then remove the Setting Lever, Yoke, Driving Wheel, Internediate Setting Wheel No.1, and the Setting Wheel

      Here's a reference photo of the Keyless Work.

      The movement is now completely disassembled.

      I hope you've enjoyed this disassembly walkthrough and found it's given you the information and confidence to tackle this tricky but rewarding quartz movement.
      I will post the assembly procedures tomorrow, Lord willing :)

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