1979 Dunbier Mechanical Caliper Spring and Bolt (Wishbone Type) | Marine Trailer Part

🔧 Product Description

Dunbier Mechanical-Caliper Return Spring and Bolt – Wishbone Type – Part Number: 1979

A wishbone-style return spring and retaining bolt for the compatible Dunbier mechanical disc-brake caliper. The formed spring applies return force to the operating mechanism while the bolt locates the assembly on the caliper.

⚙️ Key Features

• Wishbone-shaped caliper return spring
• Includes matching retaining bolt as supplied
• Restores mechanical caliper release action
• Alternative spring design to the coil-type system
• Marine trailer brake service component

📏 Specifications

• Spring type: Wishbone
• Includes retaining bolt
• Caliper version must match the original spring arrangement

🔄 Cross Reference & Related Parts

• Dunbier: 1979
• Coil-type spring: Dunbier 1977 / Mackay H3262
• Mechanical caliper: Dunbier 1971

🚤 Trailer Compatibility & Application

• Suits Dunbier mechanical calipers originally equipped with the wishbone spring
• Do not convert between spring designs without confirming caliper compatibility
• Inspect the bolt thread and spring contact points

🔌 Function

Returns the mechanical caliper operating arm and pads to the released position.

⚠️ Common Signs of Failure

• Spring is cracked, flattened or distorted
• Retaining bolt is loose or worn
• Caliper fails to release
• Spring contact surfaces are deeply grooved
• Brake drag causes excessive disc temperature

🛠️ Installation & Safety

• Secure the trailer and release brake-cable tension
• Install in the original orientation
• Use the correct locking method on the retaining bolt
• Check free caliper movement
• Readjust the brake cable after replacement

📦 Condition

• Brand new Dunbier Marine Products trailer component
• Supplied as one wishbone spring and retaining bolt
• Supplied in original or equivalent packaging