AN Male / Female Adapters

AN adapters join an AN (37-degree flare) hose end to a port with a different thread, or change one AN size to another. They are the part that lets a braided line connect to an oil cooler, fuel rail, turbo oil feed, sensor port or gauge.

Each adapter is listed by its two ends. One side is an AN male flare, from -3 upwards. The other is the thread of the port, or another AN size for a reducer. Port threads come as:

• metric, such as M10 x 1.0, M12 x 1.5 or M14 x 1.5;
• NPT, BSP or ORB.

Adapters come male-to-male or male-to-female, straight or at 45 and 90 degrees. Most are anodised aluminium in black, blue or silver; stainless steel and brass versions are there for higher temperatures or fluids where aluminium is not ideal.

Identify the port thread before ordering, ideally with a thread gauge, because metric, BSP and NPT threads of a similar size are easy to confuse.

How the adapter seals depends on the thread:

• the AN flare seals metal to metal and needs no sealant;
• NPT threads are tapered and seal on the thread itself, with a suitable sealant or tape kept off the first thread;
• metric and BSP threads seal with a copper or bonded washer;
• ORB threads seal with an O-ring.

Aluminium is softer than steel, so tighten with proper AN spanners rather than pliers, and check every joint for leaks under pressure.