I’ve added scans of Citizen’s booklet covering their 8100 and 8110 chronograph movements to the Automatic Chronograph page. It’s in .pdf format so you should be able to download it if you wish. The cover gives two great reference watch images, especially for the band used on the black cased 8100’s:
As a ‘new product digest’, and given the detail it provides including parts diagrams and lists, I presume this was given to dealers in 1972 when these movements were first produced. The link to the booklet will stay on the chronograph page, but here’s the link as well: CitizenChronographBooklet
Sweephand's Vintage Citizen Watch Blog 
Nice posting, Stephen! A wealthy reference for the Citizen fans!
Thanks Eduardo 🙂 Stephen
Hi Stephen, I have been following your blog for a couple of months and let me a tell you this, you rock! I really enjoy your posts. I woul like to know if you could explain to me by email or by a blog post how do you remove the crhonograph push buttons of these Citizen. I will be trying to bring back to life an old Citizen Bullhead and that is something I don’t have any idea how to do it. Thanks again for this particular post. I am Santiago from Argentina and this is my email (***deleted to protect privacy***)
Hi, thanks for visiting my blog and for your kind comments, they are much appreciated 🙂 Since htis is a public blog I have deleted your email address since I get to see it privately when I approve your comment.
Although I am not a watchmaker, I know that that the chrono buttons are held in placed by small ‘circlips’ inside the case. These can be pushed off to free the button, but you must be very careful not to lose the clip if it flies off suddenly! Here’s a pic showing the clip I mean:
Hope this helps!
Stephen
Hi again – that picture was rather poor, so I’ve just done another which shows the clip better:
Stephen
Hi Stephen, thanks for your answer and for deleting my email adress. And thanks again for the pictures. I’m not a watchmaker either, but I’m trying yo learn while I enjoy it así a hobby. Apart from the complete Bullhead I have a Citizen Chrono case with no movement ir dial. I’ll first try on that one! Thankyou!
You’re welcome – and good luck with it 🙂 Stephen
Stephen,
Thanks for al your interesting posts andprofond articles about the Cititzen watches: super! As I am not so familiar with Citizen watches I would like to ask a question. I became enthousiastic about the chrono’s and a while back I bought a Citizen Recordmaster (with numbers 4-570014 Y, 20400352, 63-0110 on the case back) It has a broken crystal, but I managed to find a new one. As I put on the lunette I can still move the crystal, it definitely needs a gasket? I didn’t find out what gasket to use as the old crystal was glued onto the case!. Do you know where I can find these gasket (s) or find information about the gaskets (anything will help!).
Many thanks,
Arnout
Hi Arnout, thanks for visiting my blog and for your kind comments. Apologies for my late reply, been a busy weekend! I’m afraid original parts for the Record Master models are very difficult to find. It may be that you’ll have to see if a watch maker can fit a modern gasket for now. Citizen’s part numbers are 54-0325 for the glass, and 392-0031 for the gasket. The best place to search is probably Yahoo Japan, but a great deal of patience may be needed!
Stephen
Hi! Fine thanks. I will get mine tomorrow from the watchmaker and this will be useful for the conservation of the watch.
You’re welcome
Does any one know if the dials for the oval bullhead and octagonal Bullhead are interchangeable?
Hi Chris, I believe that it would fit if you can’t source the correct dial – presume by ‘oval’ you mean model numbers67-9011/9020/9043