Westerbeke Thermostat 77°C (170°F) – 822-0377
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You have 30 days to request a return. All sale items are final sale.
The Westerbeke Thermostat 822-0377 is a genuine OEM 77°C (170°F) thermostat designed for Westerbeke marine diesel and gasoline engines as well as generator sets. This thermostat regulates coolant flow to maintain proper engine operating temperature, ensuring efficient combustion, reduced internal wear, and stable performance under load.
Calibrated to open at 77°C (170°F), this thermostat is commonly used in closed-loop (freshwater cooled) Westerbeke systems, allowing engines to run at optimal temperature for fuel efficiency and longevity.
Key Features
- Genuine Westerbeke OEM thermostat
- 77°C / 170°F temperature rating
- Maintains consistent engine operating temperature
- Designed for marine diesel and generator applications
- Corrosion-resistant construction for marine environments
- Direct OEM replacement
Engine Compatibility
Used across a wide range of Westerbeke engines and generators, including:
- Westerbeke marine diesel engines
- Westerbeke gasoline generator sets
- Universal (by Westerbeke) marine engines
Common applications include:
- 20B, 30B, 5.0 BCD series (and similar platforms)
- Various BTG / BTD / BEG generator models
✔ Typically used in freshwater/closed cooling systems
✔ May include bypass-style thermostat depending on engine model
Westerbeke thermostats are used across multiple engine families, so exact fitment must be verified by engine model or serial number.
Serial Number Fitment Notice
Westerbeke uses multiple thermostat variations across similar engine models. Always confirm compatibility using your engine model and serial number before ordering.
When This Part Needs Replacement
- Engine overheating or running hotter than normal
- Engine not reaching proper operating temperature
- Fluctuating temperature readings
- Thermostat sticking or corrosion
- Routine cooling system service
Installation Notes
- Replace thermostat gasket or O-ring during installation
- Install with spring side toward engine
- Ensure proper seating in housing
- Inspect coolant system for scale or blockage
- Verify operation after installation
Alternate / Superseded / Cross-Reference Part Numbers
- Westerbeke: 822-0377
- Equivalent / Related: 037043
- Sierra: 23-3602 (application dependent)
- Other Westerbeke refs may vary by engine model
Parts Desk Insight
Westerbeke thermostats are not one-size-fits-all even when temperature ratings match. The 77°C version is commonly used across mid-range diesel and generator units, but housing depth and bypass configuration can vary. Always match the physical design if you don’t have the original part number.
Shipping
Shipping: Ships same or next day for fast Canada wide shipping. ⚓
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.