Sierra 18-70931
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Sierra 18-70931 Product Description
Sierra 18-70931 Molded Cooling Hose - Precision-Engineered for MerCruiser 2.5L & 3.0L Engines
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.
Key Features & Benefits
- Pre-Molded Design - Precision-formed bends ensure maximum water flow and perfect alignment
- OEM Replacement Quality - Direct replacement for MerCruiser 32-96879
- Marine-Grade Construction - High-temperature resistant rubber withstands harsh marine conditions
- Enhanced Durability - Thicker wall construction provides superior longevity
- Perfect Fitment - Eliminates installation struggles with precise end alignment
- Integrated Spring - Includes internal spring for shape retention and flow optimization
Technical Specifications
| 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 |
Engine Compatibility
Direct Replacement For:
- MerCruiser 32-96879
- MerCruiser 32-47640
- MerCruiser 32-8M0071007
- Marine Power 274009
- Mallory 9-44050
Compatible Engine Applications:
- MerCruiser MCM 120/2.5L
- MerCruiser MCM 140/3.0L
- MerCruiser MCM 160/165
- OMC GM Inline engines
Installation & Service
Installation Guidelines:
- Allow engine to cool completely before beginning work
- Drain cooling system to below hose connection points
- Remove old hose and clean all connection surfaces
- Inspect hose clamps and replace if corroded or damaged
- Install new hose ensuring proper alignment at both ends
- Secure with appropriate marine-grade hose clamps
- Refill cooling system and check for leaks
- Test system operation after installation
Why Choose Sierra Molded Hoses?
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.
Signs You Need This Hose
- Visible cracking or deterioration of existing hose
- Coolant leaks at hose connections
- Hose swelling or soft spots
- Engine overheating due to restricted coolant flow
- Routine cooling system maintenance replacement
- Hose hardening or brittleness from age
Cooling System Function
This critical cooling hose serves essential functions:
- Coolant Circulation - Connects water pump output to thermostat housing
- Temperature Control - Ensures proper coolant flow for optimal engine temperature
- System Integrity - Maintains cooling system pressure and prevents leaks
- Flow Optimization - Pre-molded bends minimize flow restrictions
- Engine Protection - Prevents overheating through reliable coolant delivery
Performance Advantages
Sierra's pre-molded design provides superior performance:
- Maximum Flow Rate - Optimized bend radius maintains full coolant flow
- Precise Alignment - Eliminates stress on connections and clamps
- Reduced Installation Time - Perfect fit reduces installation complexity
- Enhanced Durability - Thicker walls resist wear and temperature extremes
- Long Service Life - Marine-grade materials provide extended reliability
Maintenance Recommendations
Service Guidelines:
- Inspect hoses annually for cracks, swelling, or deterioration
- Replace every 5-7 years or per manufacturer recommendations
- Check hose clamps for proper tension and corrosion
- Monitor coolant levels and look for signs of leaks
- Replace immediately if any signs of failure are detected
- Always replace hoses during major cooling system service
Frequently Asked Questions
Will this hose fit my specific MerCruiser engine?
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.
What makes this hose better than universal hoses?
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.
How often should cooling hoses be replaced?
Inspect hoses annually and replace every 5-7 years as preventive maintenance. Replace immediately if cracking, swelling, or leaks are detected.
Can I use regular automotive coolant hoses?
No, marine applications require hoses specifically designed for marine environments. This hose uses marine-grade rubber compounds for saltwater and temperature resistance.
What tools do I need for installation?
Basic hand tools for hose clamp removal/installation, coolant drain equipment, and new marine-grade hose clamps if originals show wear or corrosion.
Warranty & Support
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.
Save $5 when you buy the Sierra 18-70931 for only $29 from NVN Marine! Same day shipping before 3pm.
Sierra 18-70931 Technical Specifications
| Type: | |
|---|---|
| Vendor: |
Sierra Engine Parts |
| Weight: |
0.7 lb |
Sierra 18-70931 User Reviews
Sierra 18-70931 Shipping & Return
| Shipping Weight: |
0.7 lb |
|---|---|
| Box Sizes: |
2.00 (h) x 9.00 (w) x 10.00 (l) |
| Cubic Feet: |
180.0 |
| Returnable: |
Yes |
For detailed shipping policy please check our Shipping Policy and you can find our Return and Refund Policy here.