Gates 51803 Premium Molded Coolant Hose

The Gates 51803 is a factory-molded, OEM-quality coolant hose engineered for precise fit and long-lasting performance. Pre-shaped to match original equipment dimensions, this hose eliminates the guesswork of cutting or adapting straight hose, ensuring a leak-free seal from the first installation.

Gates molded coolant hoses are constructed with an EPDM tube and heat- and ozone-resistant EPDM cover reinforced with synthetic fiber knit, giving them exceptional resistance to the electrochemical degradation (ECD) that is the leading cause of coolant hose failure. ECD occurs when the hose, liquid coolant, and metal fittings form a galvanic cell, generating micro-cracks in the hose tube that allow coolant to seep in and break down the reinforcement — eventually causing failure and costly engine damage.

Key Features:

• Factory pre-molded to OEM specifications for exact fit and proper sealing
• EPDM construction resists heat, ozone, and chemical coolants
• Engineered to resist electrochemical degradation (ECD) — the leading cause of hose failure
• Specifically engineered materials resist vacuum collapse, reducing the need for internal springs
• Meets SAE 20R4 EC Class D1 requirements
• Temperature range: -40°F to +275°F (-40°C to +135°C)
• Approved for marine applications
• Aramid or rayon knit reinforcement depending on application

Gates recommends replacing hose clamps each time a new coolant hose is installed for optimal performance and a secure, long-lasting connection.