Bulkhead and other types of common fittings
Fittings are usually the last that come to mind when retrofitting a vintage or classic car or finishing a quick DIY project with your vehicle. However, these components become the most vital at the end of the job when you’re just about done but don’t have the proper fittings for specific parts. It’s best to categorize them in the most basic sense as we’ll do below in hopes of shedding some light on a problem that eludes us all.
Unlike parallel screws, the tapered nature of these fittings, it can only screw until a certain distance. The most common pipe thread that automobiles use is the American Standard Pipe Taper Thread. When the tapered thread fails to seal completely as it should, using a Teflon-based adhesive will do wonders to help it become leak-proof.
Simply put, AN stands for Army/Navy fittings which means they are components that are interchangeable and compatible with those from different manufacturers. These include adapters like bulkhead adapter and bulkhead nut fittings.
This fitting is quite unique as the flare is folded back on itself or even doubled, if you will. This style strengthens the fitting while increasing its resistance to the possibility of cracking later on. These are normally found in the brakes, transmission cooler and fuel lines, and even in power steering.
These fittings are meant for low to medium pressure purposes. They don’t require welding and thus, are easy to assemble. These are adaptable and can be used on a number of tubes but should stay far far away from the brakes.
Hydraulic adapters are used for two main things: to connect various fitting types, to connect brake lines to ports of various sizes in a dual master cylinder, or to connect standard and metric fittings.