Volvo Penta Heat Exchanger | SKU 3861786
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Volvo Penta Heat Exchanger – 3861786
OEM Part Number: 3861786
Part Type: Heat Exchanger / Oil Cooler
Application: Engine cooling system (seawater-to-coolant heat transfer)
Product Description
The Volvo Penta 3861786 heat exchanger is a critical cooling system component designed to regulate engine temperature in Volvo Penta marine engines. The heat exchanger transfers heat from the engine’s closed-loop coolant system to raw seawater, helping maintain proper engine operating temperatures during continuous marine operation.
Manufactured as a genuine OEM Volvo Penta component, this heat exchanger is engineered for durability and efficient heat transfer in demanding marine environments. It helps protect the engine from overheating while supporting reliable engine performance and long service life.
Compatible Volvo Penta Engine Types
This heat exchanger is commonly used on several Volvo Penta gasoline marine engines, including:
Volvo Penta V8 Engines
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5.0GXi-B
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5.0GXi-BF
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5.0OSi-B
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5.0OSi-BF
Volvo Penta 5.7L Engines
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5.7Gi-B / 5.7Gi-BF
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5.7GXi-C / 5.7GXi-CF
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5.7GiI-B
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5.7GXiI-C
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5.7OSi-A / 5.7OSi-AF
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5.7OSXi-A / 5.7OSXi-AF
These engines are typically used in Volvo Penta sterndrive and inboard marine applications.
How to Verify Compatibility Using Your Engine Serial Number
Volvo Penta engines include an identification plate that lists the engine model and serial number, which should always be checked before ordering cooling system components.
Typical locations for the engine identification plate include:
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On the engine block
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On the valve cover
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On the intake manifold or mounting bracket
To confirm compatibility:
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Locate the engine model and serial number on the engine identification plate.
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Check the Volvo Penta parts catalog for your specific serial number range.
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Confirm that heat exchanger 3861786 is listed for your exact engine configuration.
Because cooling system components can vary by engine revision and serial range, verifying the serial number ensures the correct heat exchanger design and fitment.
Specifications
| Specification | Details |
|---|---|
| Part Type | Heat Exchanger / Oil Cooler |
| OEM Part Number | 3861786 |
| Application | Engine cooling system |
| Approx. Length | ~10.5 in |
| Inner Diameter | ~1 in |
| Construction | Marine-grade metal heat exchanger core |
Key Features
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Genuine OEM replacement for Volvo Penta 3861786
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Designed for Volvo Penta 5.0L and 5.7L gasoline engines
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Efficient heat transfer for reliable engine cooling
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Durable marine-grade construction
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Supports stable engine operating temperature
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OEM-fit design for straightforward installation
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.