Lubricating ETA time/date movement reverse gears - HOW TO

[GenTLe]

I just want to advise something based on my experience.
Read ALL before you start unassemble your watch to discover you miss something necessary half way...

First let me explain what reverse wheels are...
They can be found only in automatic watches, and not in all of them (Seiko for instance use a cam&levers system, and also some of our 23j have the Seiko system, like the UN Maxi Marine non chrono), but definitively they are present in all ETA variants like 2824, 2836, 2834, 7750, 7751, 7752 (the gmt one) and 7753...
They looks like these:

 

They are responsible to transmit the motion of the rotor to the main spring, and work more or less like a bicycle pinion: when the rotor (your legs for the bicycle) rotates faster than the gears connected to the main spring (faster than the bicycle rear wheel), then the rotor motion is transmitted to the main spring, winding it (then your legs power is transmitted to rear bicycle wheel, increasing your speed).
Instead if the gears connected to the main spring rotates faster than the rotor (typically when the watch is on the table quiet or when you manually wind the watch with the crown), the reverse wheel disengage and does NOT transmit the motion to the rotor (like on the bicycle when you are going and stop to move your legs).
This is particularly valid for the single direction autowind like the 7750, but can be acceptable also for the bidirectional autowinding system like the 2836 where you have 2x reverse gears.

So, what may happen to these very complicated gears? Well, basically just 2 things:
1) they can lack of lubrication, or be lubricated with wrong systems.
2) they can break.
The 1st case is the most common one, and has a typical symptom: the manual winding action appear stiff, when you hand wind the watch the rotor tend to spin or really spins (typically when the watch is kept horizontally).
The 2nd case (I have an Hublot with this problem) is much more rare and makes instead the autowinding system not to work at all: the rotor just rotate but doesn't charge the main spring. Only solution for this is to replace the reverse gears.

Let's concentrate on the most common case.
So the hand wind is stiff and you want to fix it.
On 2836/2824/2834 it is not complex: you need to open the case back, then you need to remove the rotor unscrewing the big central screw here:

then you need to remove the 2 screws that keeps on the autowind bridge (1.2mm screwdriver) and lift the autowind bridge. You recognize the right screws because they are normally black. They are the ones missing from the 2 smaller holes here:

After you have removed the autowind bridge, put it upside down on a surface and remove the screw that keeps there the gears (reverse wheels and the other 2 reduction gears). Here you can see a VERY dirty autowind bridge upside down:

You should arrive to have all in bits like in this pic where you can see 3x autowind bridge disassembled:

 

Now it is time to properly clean all. For the 2 bridges I normally use a toothbrush with some soapy degreaser to do the first coarse wash, then I put all (gears, bridges and even the screw) in my ultrasonic cleaner loaded with a warm mixture of 50cl of ammonia + 36cl acetone + 14cc oleic acid + enough demineralized water to reach 1 liter and let them be cleaned for around 5 minutes.
After this I put them into demineralized water and let them rinse in the water and in the ultrasonic washer for other 3/4 minutes.
Finally you need to let everything dry over a lint-free paper (I sometime use 50°C heated oven to make the process quicker.

YES YES, I know ETA lubrication charts tells to not clean the reverse wheel... They just want you to buy new ones. I did and they were stiffer than the original asian ones!!!!

So now it's time to CORRECTLY lubricate those 2 bastards...
There are many formulas and wizard's mixtures advertised here and there as the solution to lubricate the ETA reverse wheels (considering also the 775x movements)...
I tried them all, but the only PROPER product I found to do the job is the one that ETA itself developed to lubricate their reverse wheels, and it's named "LUBETA v105" (http://hiro.alliancehorlogere.com/en/Under_the_Loupe/Lubeta_V105). It is not that cheap and I found few places that sells small amount of them.
My source is this: http://www.ebay.com/itm/400720621082
Do not mess up with the V106 which is for something else (http://hiro.alliancehorlogere.com/en/Under_the_Loupe/Lubeta_V106) and that can be substituted safely with a tiny amount of HP1300.
Wet well the reverse gears with this V105 product (sometimes I even immerse the reverse gears in the solution) and then let the reverse gears to dry completely over a surface (better a clean metallic one: don't use something that can absorb it or that could be melted by the V105 thinner).

Then follow this chart to reassembly everything, and you will find out that the hand wind will be smooth like a brand new gen ETA (regardless it's an asian or eta movement):

One last tip: when you are mounting back the rotor, do NOT tight fully the central screw: as soon as it start to get tight, make the rotor to rotate: sometimes it doesn't engage properly with the wheels of the autowind bridge, and if you tighten it in that state you can bend the wheels and make a mess...

Finally: 775x is similar, but it is MUCH more difficult to unassemble and reassemble because there are a lot of bits to align to fit the autowind bridge, so I don't suggest anyone to try if it is not really confident to work on watch movements...). See here on the other RWG -> http://www.rwg.bz/board/index.php?showtopic=1039

Ah, very last thing: while on the 2836/2824/2834 you can fit gen ETA spare parts, with 775x you can't (tried today with the mentioned Hublot): it seems that it fits, but the reverse gear pinions are 0.2mm for the asian ad 0.38mm for the ETA/Valjoux and even if you can then reassemble everything apparently well, then the rotor doesn't engage the reverse wheel properly...

Cheers, GenTLe 

[Lolo1972sg]

This is excellent!

[GenTLe]

This is excellent!

Welcome!

[Dlf]

Excellent !

[SSTEEL]

Great tutorial A, well done.!  I get my supply from cousinsuk..

 

https://www.cousinsuk.com/product/eta-lubeta-v105?code=O39844

[jakethemouse]

Thanks Gentle for posting on my RWG thread.

Used the search box here and your tutorial is exactly what I need

Edited May 23, 2016 by jakethemouse

[GenTLe]

Welcome Jake!

[jpohl402]

Wow, excellent excellent excellent!!

Many thanks!!

Now, if only I could do this myself... Lol

[Rolexman]

Great write up. The reason reversing wheels are stiff is not because the pivots and/or clicks are dry or gummed up. It is because there is too much debree or oil between the brass plates and clicks. The clearance between them is nihil. So even the wrong cleaning solution that will leave the tiniest amount of settlement can make the turning of the brass plates feel 'stiff'. Also solutions that will make the brass react can have the same effect. That's why ETA recommends replacement. They are too finicky to service for most watchmakers.

 

PS: I usually throw them a couple of minutes in some naphtha and afterwards put the tiniest amount of 9010 on the ETA spots. Usually does the trick. A proper oiler and technique is essential of course. Sometimes it doesn't work and I don't mess around. I than just replace the f#ckers.

[GenTLe]

Great write up. The reason reversing wheels are stiff is not because the pivots and/or clicks are dry or gummed up. It is because there is too much debree or oil between the brass plates and clicks. The clearance between them is nihil. So even the wrong cleaning solution that will leave the tiniest amount of settlement can make the turning of the brass plates feel 'stiff'. Also solutions that will make the brass react can have the same effect. That's why ETA recommends replacement. They are too finicky to service for most watchmakers.
 
PS: I usually throw them a couple of minutes in some naphtha and afterwards put the tiniest amount of 9010 on the ETA spots. Usually does the trick. A proper oiler and technique is essential of course. Sometimes it doesn't work and I don't mess around. I than just replace the f#ckers.

Thanks Rolexman! I found out that one of the best cleaning way is warm isopropyl alcohol (put some hot water in the ultrasonic cleaner and a little jar with the alcohol, bain-marie way) and give a full 5min ultrasonic shake

[SSTEEL]

Or lighter fluid will do the trick also Alex.

[ceejay]

I had to replace a couple recently from a Tudor (ETA) damn expensive little wheels!

VP105 is my goto lube for reversing wheels. I used to use RM's method of a fine oiler and 9010 but my hands aren't steady enough these days

 

Nice write up 'G'