Volvo Penta Thermostat 3856961
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
The Volvo Penta 3856961 Thermostat is a genuine OEM cooling system component designed to precisely regulate engine temperature in Volvo Penta marine engines.
Engineered for consistent thermal control, this thermostat ensures proper engine warm-up and maintains optimal operating temperature under load. It helps prevent overheating, improves fuel efficiency, and supports long-term engine reliability in harsh marine environments.
Built to Volvo Penta’s exact specifications, it delivers dependable performance across a range of modern marine engine platforms.
Key Features
- Genuine Volvo Penta OEM part
- Maintains accurate engine operating temperature
- Ensures reliable cooling system performance
- Designed for marine gasoline and diesel engines
- Corrosion-resistant marine-grade construction
Engine Compatibility
Volvo Penta Marine Engines
Commonly used on:
- Volvo Penta D3 diesel engines
- Volvo Penta gasoline engines (various models)
➡️ Found across multiple modern Volvo Penta cooling systems
Serial Number Fitment Notice
Fitment depends on:
- Engine model and variant
- Cooling system configuration
⚠️ Always confirm compatibility using your engine serial number before ordering.
Specifications
- Part Number: 3856961
- Type: Engine thermostat
- Function: Regulates coolant temperature
- Construction: Marine-grade metal and composite assembly
What’s Included
- Thermostat (seal/gasket sold separately unless specified)
When This Part Needs Replacement
Replace the thermostat if you notice:
- Engine overheating
- Engine running below normal temperature
- Fluctuating temperature readings
- Reduced engine efficiency
Installation Notes
- Replace seals or O-rings during installation
- Ensure correct orientation in housing
- Inspect cooling passages for debris or corrosion
- Test engine temperature after installation
Alternate / Superseded Part Numbers
OEM Cross References
- Volvo Penta: 3856961
Shipping
Shipping: Ships same or next day for fast Canada wide shipping. ⚓
💡 Parts Desk Insight
This style thermostat is common on newer Volvo setups—if temps are inconsistent, this is usually the first place to look 👍
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.