Valjoux 7733 Service

[Khan]

Hello

I have for a long time been excited about servicing a chronograph. Are there any cautions I should be aware of? I'm pretty much used to service different manual and automatic swiss movements. I can't find a video or manual for disassembly procedure. What movement is it familiar with? 

[oldhippy]

Mark has very good videos of servicing a breitling venus 175.

I suggest you start with that. If you get stuck you can refer to Marks videos.Here is a link for the first part.

 https://www.youtube.com/results?search_query=breitling+venus+175

[watchweasol]

Hi You will probably find these tech sheets useful doing the V7733 . all the best

1060_valjoux 7733, 7734, 7736 Pages 1-5.pdf 1061_valjoux 7733, 7734, 7736 Pages 6-10.pdf 1062_valjoux 7733, 7734, 7736 Pages 11-15.pdf

[nickelsilver]

The 7733 is a pretty easy chrono, especially with a the tech sheets. The thing I've seen that trips people up is the start/stop lever is pivoted and on two planes, and has an integral spring. It can seem counterintuitive to get in place correctly so pay attention when disassembling how it's setup.

[Delgetti]

Here are some pics I took on a 7734 (7733 is the same just without date). And I agree that the start stop lever is really tricky. Before disassembly have a close look from the side, keep the layering in mind and take some photos. 

 

[Khan]

Hi again! 

Regarding chronograph runner:

I managed to take the movement apart and assemble it, thanks to the knowledge shared and available. It runs like a dream without engaging the chrono. When chrono starts, it still runs good for 10-20 sec. And stops immediately. I can't see what's preventing it to run. The train wheels should be aligned enough. No lubrication in forth wheel, minute runner and sliding gear wheel. A drop of 9010 on top of chrono runner and lower pivot. It's black on the pivot shaft, is it worn out (teeth seems intact)? And should I use 9501 on the chrono and minute runner contact area? Its shown in service manual but not mentioned elsewhere here. 

Edited September 25, 2019 by Khan

[nickelsilver]

My first guess would be the depthing of the intermediate driving wheel to chrono runner is too deep. The eccentric to adjust is in red circle.

[Khan]

Hi Nickelsilver

Your guess is on spot. Now less depth and it runs as good as without chrono function. You made my day, thanks alot.