ETA 2893-1 Service Walkthrough - Part 1 - Disassembly

[sstakoff]

Service Walk Through – ETA 2893-1 / Hamilton Khaki: Part 1 - Disassembly

 

This is part 1 of my service of a Hamilton Khaki – dual time zone automatic based on the ETA 2893-1 movement. I purchased the watch on eBay and it runs for a short time then stops. Looks like it could use a good cleaning.

Note that the part numbers in the images and text are consistent with those found in the ETA technical document for this movement. Disassembly of this movement is quite straightforward. The only "special" tool you need would be an oscillating weight bolt tool - and you only need this if you intend to remove the ball bearing assembly from the oscillating weight, which really isn't required. In this tear down I do use the tool - only because I recently acquired it and wanted to see how it worked

Off we go....

 

The dial shows evidence of some sloppy workmanship in the watch's past – several scratches from prior hand removal.

 

Here you see the back of the 2893-1 with its automatic rotor - nicely signed Hamilton.

 

Preparing to remove the hands – with a safety sheet in place.

 

After removing the dial, remove the dial support ring. This ring keeps the dial the proper distance from the second timezone disc. Without it, the disc will rub against the dial.

 

Remove the second timezone disc from the center. This is a bit tricky as there’s no obvious place to grip it. I used two very small screwdrivers on each side to lift the indicator straight up. Be careful not to scratch it!

Disc removed.  Note the following parts: Hour Wheel (42); Hour Indicator Driving Wheel (43);  Corrector Setting Wheel (44); Additional Indicator Maintaining Plate (41)

 

 

Pop off the dial washer – note that you cannot simply lift the hour wheel (42) off at this point. It is held in place by the hour indicator driving wheel (43).

 

I remove the hour indicator driving wheel (43) followed by the corrector setting wheel (44).

 

The hour wheel (42) is now simply lifted off, followed by the additional indicator maintaining plate (41).

 

Next components to remove are the Date Indicator Maintaining Plate (40) and the Minute Train Bridge (35).

 

We move on to remove the Intermediate Date Wheel (39). The Date Jumper (38) has also been exposed when we removed the maintaining plate, so we remove it. Finally, we remove the Date Indicator (37) and the Date Indicator Driving Wheel (36).

Now on to some of the motion and keyless work. We remove the Minute Wheel (34),  Cannon Pinion with Driving Wheel (33),  Double Corrector (32) and Date Corrector Intermediate Setting Wheel (31).

 

 

Before dealing with the rest of the keyless work, we flip the movement over and remove the automatic work. After removing the 3 blue screws we lift the entire unit up gently by the Oscillating Weight (28).

 

With the automatic work out of the way – I notice that the Stop Lever (Hack) is missing! Will try and source one.

 

Back to the automatic work. Removing these 3 screws will allow the oscillating weight to come off the Automatic Framework (21) and its components.

 

Using the appropriate Bolt tool (pictured with the red handle) – I remove the Oscillating Weight Bolt (28-3) and free the Ball Bearing (28-2) from the Oscillating Weight (28-1). There was no compelling reason to disassemble this portion of the movement.

 

With the Oscillating Weight out of the way, remove the Auxiliary Reverser (27).

Flip the unit over once again and remove the screw and Automatic Device Lower Bridge (26).

 

Remove the Reverser (25), Reverser Wheel (24), Reduction Wheel (23) and Intermediate Reduction Wheel (22).

A view of the underside of these components

 

Remove the single screw and gently lift off the Balance Assembly (20) with the Balance Complete (19).

Carefully let the power down by releasing the Click (12-6) and slowly letting the crown wind down.

 

 Remove the Pallet Bridge (18) and Pallets (17).

 

Remove the Train Wheel Bridge (16).

Remove the Fourth Wheel (15), Third Wheel (14) and Escape Wheel (13).

 

Remove the 3 screws and the Barrel Bridge (12)

 

Flip the bridge over and lift off the Ratchet Wheel Driving Wheel (12-2)

 

Remove the screw and the Click Plate (12-7), followed by the Click (12-6), Intermediate Ratchet Wheel (12-5), Intermediate Crown Wheel (12-4) and Crown Wheel (12-3). Note that the Intermediate Crown Wheel is under the Click Plate. When I removed the plate, the wheel was stuck to it due to some old oil.

 

Here you can see the Intermediate Crown Wheel as it was stuck.

 

This shows the proper placement of the wheels.

 

Remove the Ratchet Wheel (11), the Mainspring Barrel (10) and Intermediate Wheel (9). Note the scrap of tissue that found its way onto the movement. I was so focused on taking pics that I didn’t notice J

 

Pop the lid off the barrel.

 

Remove the mainspring arbor

 

And finally, remove the mainspring

 

The movement side is now completely bare. Let’s flip it over and finish off the keyless work.

 

Unscrew and remove the Setting Lever Jumper (8), Yoke (7) and the Setting Lever (6)

Remove the Date Corrector Operating Lever (5), Winding Stem (4), Winding Pinion (3) and the Sliding Pinion (2)

All stripped down

 

Ready for the Ultrasonic!!!

 

 

Hope you enjoyed this.

 

 

 

 

Edited July 12, 2016 by sstakoff

[anilv]

great post!

[clockboy]

Nice walkthrough interesting movement hope you can source the parts.

[Geo]

You.uve done an great job and your photos are excellent.  Unfortunately your captions don't all match up with your illustrations.  It would be a good idea to correct this and re-post.  The original can then be deleted.

[bluebottle466]

Great , thanks very much for showing us noobs how to tackle these watches .

[sstakoff]

1 hour ago, Geo said:

You.uve done an great job and your photos are excellent.  Unfortunately your captions don't all match up with your illustrations.  It would be a good idea to correct this and re-post.  The original can then be deleted.

That figures! Was a bit of an operation trying to coordinate the offline text with images. I will sort it out today at some point!

 

[Watchtime]

Was looking for a way to remove the rotor of an 2892A2 and came accross this, thanks for sharing

[Nucejoe]

Excellent presentation.