Only had my 6138-8030 and this guide has already helped!
Thank you Polly!!!
I received my 6138-8030 yesterday and noticed a couple issues straight away.
Firstly, the second hand would not make it all the way around the dial. I found that the inner seconds bezel was loose from the dial and the second hand was being stopped by it.
Next, there was a fleck of dried glue floating around under the crystal.
I decided to disassemble up to the point where I could clean the dial and reattach the inner bezel. Once apart and both tasks completed, I attempted to reinstall the winding stem/crown, but no amount of fiddling seemed to work. Researching, I found this guide and the instruction: "To fix this problem you will need to insert the stem at an angle to push into the end of the clutch (not enter its hole) this will then drag the yoke from under the setting lever and allow the setting pin to re-enter the stems setting groove."
This worked and the rest of the reassembly proceeded unhindered.
The wound watch has kept good time for the last 24hrs but I have yet to put it on the timegrapher.
Overall I am impressed and excited about the quality of my first Japanese 1970s chronograph and looking forward to collecting and working on more.
Thanks again!
Sincerely,
MjB