Welcome to the board!
I am not sure where to find a internal breakdown other than the service manual.
Normally the fine work such as internal injector work is best left to a speciality shop. Proper injector setup along with proper injection pump timing makes all the difference in your diesel's performance, longevity and fuel economy. It also make a difference in emmissions do we can all breath a little easier as well.
Problem is too fold really.
1) Unless you have access to a ultrasonic cleaner it is darn near impossible to clean the injector nozzels as the passeges are just too fine. You cannot use a wire to clean them as they are finer than that and they most likely will be damaged.
2) There is no way to bench set up a injector, IE no static adjustments so to speak. There are however base adjustments when you are assembling and then checked and verified in two ways, both requiring a special tool;
A) Pop off pressure - you pump up the tool, read the guage where the injector opens. Too low, add shims, too high, subtract shims. Although some injectors use differing springs, they are rarer.
B) Spray pattern, again using the special tool to verify the proper spray pattern. This also verifies proper injector nozzel operation and that the cleaning of the fine passages was succesful.
Most diesel shops if you provide them the pop off and pattern specs can do this for you. Speciality injector shops can do it all, you take in crusty old injectors and get back properly functioning injectors.
At least this is the accepted, proffesional and knowlegable way of approaching injector repairs.
David
