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Dayco 87665 HVAC Heater Hose
Dayco Small I.D. Heater Hose 87665
Dayco 87665 is a Small I.D. Heater Hose built for heater and coolant routing where a 5/8 in. inside diameter is required at both ends. Made from EPDM and finished in black, this HVAC heater hose is specified to SAE J20R3 Class D-1 and SAE J1684 Type EC standards for service in the listed applications.
Key Features
- Part number: 87665
- Brand line: Dayco Small I.D. Heater Hose
- EPDM construction for heater hose service
- Black finish
- 5/8 in. inside diameter at End 1 and End 2
- Single I.D. hose design
- SAE J20R3 Class D-1 and SAE J1684 Type EC specification
- No heat shield and no protective sleeve
Fitment and Application
- Fits 1994-1995 Ford Mustang, Heater To Pipe-2; fits vehicles without air conditioning; Small I.D. Heater Hose.
- Fits 1986-1992 Ford Mustang, Heater To Pipe-2; fits vehicles without air conditioning; Small I.D. Heater Hose.
- Fits 1993 Ford Mustang, Heater To Pipe; 5/8 in.; Small I.D. Heater Hose.
- Fits 1986-1987 Ford Taurus, Heater To Engine; Small I.D. Heater Hose.
- Fits 1986 Mercury Capri, Heater To Pipe; fits vehicles without air conditioning; Small I.D. Heater Hose.
- Fits 1986 Mercury Sable, Heater To Engine; Small I.D. Heater Hose.
- Fits 1980 Toyota Pickup, Engine To Carburetor; Small I.D. Heater Hose.
This part cross-references Ford E6ZZ-18472-B and Gates 18804 for the same application.
Detailed Description
Dayco’s Small I.D. Heater Hose line is built for compact coolant and heater routing where a consistent 5/8 in. hose size is required. The EPDM rubber construction helps the hose serve in underhood heating and cooling circuits, while the SAE J20R3 Class D-1 and SAE J1684 Type EC specifications align it with common heater hose requirements. Dayco 87665 is a direct-fit option for select Ford Mustang, Ford Taurus, Mercury Capri, Mercury Sable, and Toyota Pickup applications listed above.
What It Helps Address
- Cracked or aged heater hose material
- Coolant seepage at a worn hose section
- Restricted heater circuit flow from deteriorated hose walls
- Incorrect hose size for 5/8 in. heater connections
- Replacement needs for heater-to-pipe, heater-to-engine, or engine-to-carburetor routing
Installation Notes and Tips
Verify the hose path, end diameters, and routing position before installation. This hose is listed for specific applications including heater-to-pipe, heater-to-engine, and engine-to-carburetor locations, so match the vehicle configuration and note that some Mustang and Capri applications are for vehicles without air conditioning. Inspect adjoining pipes, clamps, and fittings for wear before installing the new hose.
Quality Assurance
Dayco manufactures this heater hose to published SAE specifications for the listed applications. The product line is focused on small inside diameter heater hose service, giving buyers a specification-based replacement for confirmed vehicle fitment.
| Brand | Dayco |
| Part Number | 87665 |
| Position | Small I.D. Heater Hose, Heater To Pipe-2, Heater To Pipe, Heater To Engine, and Engine To Carburetor |
| Material | Epdm |
| Color | Black |
| End 1 Inside Diameter | 5/8 |
| End 2 Inside Diameter | 5/8 |
| Contains Heat Shield | N |
| Contains Protective Sleeve | N |
| Hose Type | Single i.d. hose |
| SAE Specification | Sae j20r3 class d-1, sae j1684 type ec |
| Trunk Height | 9 |
This part fits 15 vehicles. Search below:
| Year | Make | Model | Liters | Cylinders | Position | Notes |
|---|---|---|---|---|---|---|
| 1995 | Ford | Mustang | 5.0L | V8 | Heater To Pipe-2 | Fits vehicles without air conditioning.; Small I.D. Heater Hose |
| 1994 | Ford | Mustang | 5.0L | V8 | Heater To Pipe-2 | Fits vehicles without air conditioning.; Small I.D. Heater Hose |
| 1993 | Ford | Mustang | 5.0L | V8 | Heater To Pipe | 5/8 In.; Small I.D. Heater Hose |
| 1992 | Ford | Mustang | 5.0L | V8 | Heater To Pipe-2 | Fits vehicles without air conditioning.; Small I.D. Heater Hose |
| 1991 | Ford | Mustang | 5.0L | V8 | Heater To Pipe-2 | Fits vehicles without air conditioning.; Small I.D. Heater Hose |
| 1990 | Ford | Mustang | 5.0L | V8 | Heater To Pipe-2 | Fits vehicles without air conditioning.; Small I.D. Heater Hose |
| 1989 | Ford | Mustang | 5.0L | V8 | Heater To Pipe-2 | Fits vehicles without air conditioning.; Small I.D. Heater Hose |
| 1988 | Ford | Mustang | 5.0L | V8 | Heater To Pipe-2 | Fits vehicles without air conditioning.; Small I.D. Heater Hose |
| 1987 | Ford | Mustang | 5.0L | V8 | Heater To Pipe-2 | Fits vehicles without air conditioning.; Small I.D. Heater Hose |
| 1987 | Ford | Taurus | 2.5L | L4 | Heater To Engine | Small I.D. Heater Hose |
| 1986 | Ford | Mustang | 5.0L | V8 | Heater To Pipe-2 | Fits vehicles without air conditioning.; Small I.D. Heater Hose |
| 1986 | Ford | Taurus | 2.5L | L4 | Heater To Engine | Small I.D. Heater Hose |
| 1986 | Mercury | Capri | 5.0L | V8 | Heater To Pipe | Fits vehicles without air conditioning.; Small I.D. Heater Hose |
| 1986 | Mercury | Sable | 2.5L | L4 | Heater To Engine | Small I.D. Heater Hose |
| 1980 | Toyota | Pickup | Engine To Carburetor | Small I.D. Heater Hose |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
This part directly replaces or is cross-referenced with the following part numbers:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.