Radiator Adapters

Radiator adapters are the small parts that hold a radiator in place and connect it to the rest of the cooling system. Two kinds are listed: aluminium radiator stay sets made for particular cars, and universal radiator fittings with either a 1.5-inch hose connection or a 16AN end.

Most radiators sit on rubber isolators at the bottom and are held at the top by stays. The stays stop the radiator moving under braking, cornering and kerb strikes, while their rubber bushes keep engine and body vibration out of the core. A loose or broken stay lets the radiator rock, and over time that movement can crack tanks and tube joints.

The fitting decides what the coolant line connects to. A 1.5-inch connection takes a conventional slip-on hose and clamp. AN sizes count in sixteenths of an inch, so a 16AN fitting suits a line of about one inch, joined with a threaded hose end.

Choose by the job the part has to do.

• Stay sets: aluminium stays in gold, pink, blue and red, listed by model and years in the title. Where the factory stays are plastic, aluminium ones do not soften with heat or crack with age.
• Hose connection: the 1.5-inch fitting, for silicone or rubber hose with clamps.
• AN connection: the 16AN fitting, for a hose end on braided or push-on line, which suits long runs and lines passing through bulkheads.

Size the coolant lines to the engine’s outlet, so the connection never becomes the restriction in the circuit. Fit stays with their rubber bushes in place, and tighten them only until the radiator is held firmly without being squeezed. Replace hardened bushes, because a radiator clamped metal-to-metal passes every vibration into its tanks.

After fitting a new connection, fill and bleed the system, then check the joint for weeping both cold and at full temperature. Re-check the stay bolts after the first drive, as new bushes settle.