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Ensure reliable cooling system performance with the Sierra 18-70931 Molded Cooling Hose. Specifically designed for MerCruiser 2.5L and 3.0L engines, this precision-molded hose connects the circulating water pump to the thermostat housing, providing optimal coolant flow and maximum durability in marine environments.
| Manufacturer: | Sierra Engine Parts |
| Part Number: | 18-70931 |
| UPC Code: | 808282145934 |
| Application: | Circulating Pump to Thermostat Housing |
| Construction: | Pre-Molded with Internal Spring |
| Material: | High-Temperature Marine-Grade Rubber |
Direct Replacement For:
Compatible Engine Applications:
Installation Guidelines:
Sierra Marine has been manufacturing premium cooling system components for over 40 years. Their molded hoses are engineered to meet or exceed OEM specifications, using advanced rubber compounds that provide superior heat resistance and durability. The pre-molded design eliminates installation challenges while ensuring optimal coolant flow through precise bend geometry.
This critical cooling hose serves essential functions:
Sierra's pre-molded design provides superior performance:
Service Guidelines:
This hose fits MerCruiser MCM 120/2.5L, 140/3.0L, and 160/165 engines, replacing part number 32-96879. Verify your engine model and part number for exact compatibility.
The pre-molded design ensures perfect fit, optimal coolant flow, and eliminates installation struggles. It's specifically engineered for your engine's cooling system geometry.
Inspect hoses annually and replace every 5-7 years as preventive maintenance. Replace immediately if cracking, swelling, or leaks are detected.
No, marine applications require hoses specifically designed for marine environments. This hose uses marine-grade rubber compounds for saltwater and temperature resistance.
Basic hand tools for hose clamp removal/installation, coolant drain equipment, and new marine-grade hose clamps if originals show wear or corrosion.
Sierra Marine Parts are backed by manufacturer warranty against defects in materials and workmanship. Professional installation and regular inspection ensure optimal performance and system reliability.
Ships within 48 hours · Estimated delivery Jun 20 - Jun 25
US$40
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