Dayco 87731 HVAC Heater Hose

Dayco Small I.D. Heater Hose 87731

Dayco 87731 is a Small I.D. Heater Hose built for HVAC heater hose service where a 5/8 in. inside diameter is required at both ends. Made from EPDM and finished in black, this single I.D. hose is specified to SAE J20R3 Class D-1 and SAE J1684 Type EC standards for heater circuit use.

Key Features

• EPDM construction for heater hose applications
• 5/8 in. inside diameter at End 1 and End 2
• Single I.D. hose design for straightforward routing
• Black finish for a clean OE-style appearance
• SAE J20R3 Class D-1 and SAE J1684 Type EC specification
• Dayco Small I.D. Heater Hose line for HVAC hose replacement

Product Details

The Dayco Small I.D. Heater Hose line is built for vehicle heater and coolant transfer routing where a smaller diameter hose is required. Part number 87731 is a 5/8 in. EPDM heater hose with no heat shield and no protective sleeve, making it a direct material-and-size match for service work that calls for a single I.D. hose. This hose is listed with fitment for 2004-2006 Toyota Sienna, tee to engine; 2002-2005 Ford Explorer, valve to water pump; 2002-2005 Mercury Mountaineer, valve to water pump; and 1991-1993 Mazda B2600, heater to pipe, along with additional Mazda B2600 and Dodge Colt applications. If you are replacing a worn heater hose on a Toyota Sienna, Ford Explorer, or Mercury Mountaineer, Dayco 87731 provides the correct 5/8 in. hose size for the specified routing.

This part cross-references Ford 1L2Z-18472-LA and Motorcraft KH47 for the same application.

Common Problems This Hose Can Address

• Cracked or hardened heater hose material
• Coolant seepage at a 5/8 in. hose connection
• Restricted heater coolant flow from deteriorated hose walls
• Incorrect hose diameter during heater hose replacement
• Routing issues on tee-to-engine, valve-to-water-pump, or heater-to-pipe connections

Installation Notes

Verify the hose routing, end diameter, and connection points before installation. Dayco 87731 is a 5/8 in. heater hose, so confirm the vehicle uses the same inside diameter at both ends and matches the listed position, such as tee to engine, valve to water pump, heater to pipe, or heater to engine. Inspect adjoining fittings, clamps, and coolant passages for wear or corrosion before installing the new hose.

Quality Assurance

Dayco 87731 is manufactured to SAE J20R3 Class D-1 and SAE J1684 Type EC requirements, supporting heater hose service where those specifications are called for. The EPDM construction and OE-style fitment references make it a technical replacement choice for listed applications.