Know-How Notes: Braided Hose End Guide
Braided hoses are often necessary for high-pressure applications, such as power steering lines and some fuel systems. While OEM application hoses can be purchased assembled, sometime you have to build your own. Most NAPA Auto Parts Stores carry a wide variety of braided hoses and fittings, including the kind that you can install yourself.
There are three common types of these hose ends; compression, threaded, and crimp. Your application, hose type, and equipment will determine what you need to use. Hydraulic hose ends are called JIC or AN fittings. JIC ends are steel, AN fittings are aluminum. They are interchangeable as they both use 37-degree flares (DO NOT attempt to install a JIC or AN fitting onto a 45-degree line, it will ruin both lines and leak). AC hose ends come in several different types, all of which require O-rings to seal.
Crimped Hose Ends
Crimp terminals are the most common type of high-pressure fitting that you will encounter. These are assembled fittings that in most instances will require a crimping tool that you won’t have access too, so you have to have the work done for you. The crimping tool is a hydraulic machine that compresses the fitting over the hose, permanently bonding the two parts together. Applications for these hoses are hydraulic or gas (not fuel) transfer hoses, such as power steering, brakes, and air conditioning (A/C).
Power steering and brake lines require extreme pressure handling, over 2,000 psi. These hoses need the big machine. A/C hoses see much lower pressures, in the 150-300 psi range. These fittings can be assembled with a hand-operated crimping tool.
Crimped fittings do not have any type of swivel, so they have to be assembled with the fitting correctly oriented to each other. This can be very real problem if you just guess, because your hoses will not line up. Braided hose is very stiff, it bends, but you can’t twist it. It is always recommended that you take the fittings and the hose to the vehicle, pre-installed the fittings on the hose, lightly thread the fittings to the components, and then mark each fitting to the hose with a marker. Then you can take the parts back to the store and have them crimped in place. This is a critical step that you do not want to skip.
Threaded Hose Ends
DIYers can build their own hoses using threaded-style fittings that thread together. There is a threaded collar which slides or is threaded onto the hose, which is then pushed onto the main fitting and the assembly is threaded together. These work really well for all high-pressure applications such as power steering. These fittings are not available for A/C, which require crimped fittings. There are most common and easiest to work with hose ends for DIYers. Watch out for your fingers, as the stainless wires will get you and it hurts.
Because these are so common, we have a complete assembly tutorial for you here:
Compression Hose Ends
Compression fittings are similar to threaded fittings, but instead of a nipple inside the main fitting, there is a ferrule. These fittings are commonly used with Teflon braided hoses, which has a hard plastic tube instead of a rubber hose in the center. A threaded collar slides over the hose, then the stainless braid is carefully pulled away from the plastic tube. A ferrule slides over the tube, and the fitting is pressed against the ferrule while the collar is thread to the fitting, compressing the tube, providing a leak-proof seal. These ferrules are typically made of brass, and are one-time use only, you can’t take them apart and re-install them (you will end up with a bad leak if you try). These fittings and hoses are commonly used for power steering and brake applications.
Building your own hoses is not complicated, but it does require some patience, especially with the compression fittings, those ferrules can be a real bear to work with. When in doubt, visit your local NAPA Auto Parts Store for assistance with building your new hoses.
Check out all the belts and hoses available on NAPA Online or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on braided hose end options, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.