Hello Frank, The instructions supplied with these guns as new are very basic, it may be better to look a T W Chambers website, where they have exploded diagrams of all models, which can be printed off and studied...they also sell spares.
...just click on BSA and then your gun.
There is also a book by Q Cobham, about air rifle repair, I think it is out of print, but they appear on various book websites like abe books, or on ebay from time to time.
The title is;
Air Rifle, and Air Pistol maintenance and repair,
Perfect Paperback: 208 pages
Publisher: mini-maxi publications (May 2006)
Hope some of this is of interest / help, I am sure your problem is a simple one, and also that it is easily fixable, have you tried near you to contact an air rifle club or gunshop that maybe could help?
Best regards, Eddie