Dayco 87609 HVAC Heater Hose

Dayco Small I.D. Heater Hose 87609

Dayco 87609 is a Small I.D. Heater Hose built for HVAC heater hose service where a dual inside diameter is required. Made from EPDM and finished in black, it is sized with a 3/4 in. inside diameter on one end and 5/8 in. on the other for specific heater circuit routing.

This Dayco Small I.D. Heater Hose line is used for direct-fit heater hose routing in applications that call for a reduced-diameter connection between the heater core, pipe, tee, or intake manifold. Part number 87609 is listed for select Buick Roadmaster, Chevrolet Caprice, Chevrolet Impala, Ford Escort, Mercury Lynx, Mercury LN7, Dodge Caravan, and Plymouth Voyager applications.

Key Features

• EPDM construction for heater hose service
• Dual I.D. hose design with 3/4 in. and 5/8 in. ends
• Black finish for a factory-style appearance
• Meets SAE J20R3 Class D-1 and SAE J1684 Type EC specifications
• Small I.D. heater hose configuration for select HVAC routing
• Dayco part number 87609

Detailed Description

Dayco 87609 is an HVAC heater hose engineered for applications that require a small inside diameter transition in the cooling and heater circuit. The EPDM hose material is suited for heater hose use, while the dual I.D. layout supports connections where one end must step from 3/4 inch to 5/8 inch. This makes it a practical replacement for vehicles using a tee, pipe, valve, or intake manifold heater hose path. It is listed for 1994 Buick Roadmaster, 1994 Chevrolet Caprice, 1994 Chevrolet Impala, 1984-1986 Dodge Caravan, 1984-1986 Plymouth Voyager, and select 1982-1986 Ford Escort, Mercury Lynx, and Mercury LN7 applications. This part cross-references ACDelco 18005L and Gates 18076 for the same application.

What It Helps Fix

• Cracked or hardened heater hose sections
• Coolant seepage at small-diameter hose connections
• Restricted heater flow caused by deteriorated hose material
• Incorrect hose sizing at tee, pipe, or valve connections
• Loss of heater performance from aging HVAC hose routing

Installation Notes and Tips

Verify the required end diameters before installation: 3/4 in. on one end and 5/8 in. on the other. Match the hose routing to the vehicle position listed for your application, such as Tee To Pipe, Pipe To Tee, Valve To Intake Manifold, or Heater To Pipe. Confirm the vehicle’s air conditioning and heater equipment notes before ordering, especially on Ford Escort, Mercury Lynx, Mercury LN7, Dodge Caravan, and Plymouth Voyager applications. Inspect adjoining pipes, tees, and clamps for wear before installing the new hose.

Quality Assurance

Dayco manufactures this heater hose to SAE J20R3 Class D-1 and SAE J1684 Type EC specifications for heater hose service. The EPDM construction and application-specific sizing support consistent fitment across the listed Buick Roadmaster, Chevrolet Caprice, Chevrolet Impala, and other covered vehicles. Part number 87609 is built for direct replacement use in the specified HVAC hose locations.