Thermostat for Volvo Penta AQ165A, AQ170A/B/C and BB165/BB170 Engines – 130°F (54°C)
Thermostat for Volvo Penta AQ165A, AQ170A/B/C and BB165/BB170 Engines – 130°F (54°C) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
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Thermostat for Volvo Penta AQ165A, AQ170A/B/C and BB165/BB170 Engin...
Thermostat for Volvo Penta AQ165A, AQ170A/B/C and BB165/BB170 Engines – 130°F (54°C) is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket thermostat is intended for specific Volvo Penta stern-drive and out-drive applications, including the AQ165A, AQ170A/B/C, BB165 and BB170 engine models. It is designed to regulate engine coolant temperature and begins opening at approximately 130°F (54°C), the temperature specified for this application.
This product is a single replacement thermostat, not a complete thermostat service kit. Use the reference numbers and engine-model information below to compare the replacement with the thermostat currently installed on your engine.
- Application: Volvo Penta stern-drive and out-drive marine engines.
- Opening temperature: approximately 130°F (54°C).
- Replacement references include Volvo Penta 875791 and 831040.
- Sold as one thermostat; gasket and other installation hardware are not specified as included.
Part Number Matrix
The following numbers are reference and interchange information for identifying the correct replacement. Confirm the complete engine application before ordering.
| Brand | Part Number | Notes |
|---|---|---|
| Volvo Penta | 875791 | OEM reference |
| Volvo Penta | 831040 | OEM reference |
| Sierra | 18-3663 | Aftermarket reference listed for 130°F applications; replaces 875791 |
Engine & Model Compatibility
The available application references identify the following Volvo Penta engine models. Model, cooling-system configuration and thermostat temperature must all match the original application.
| Brand | Model | OEM Reference | Opening Temperature | Notes |
|---|---|---|---|---|
| Volvo Penta | AQ165A | 875791 | 130°F (54°C) | Marine stern-drive/out-drive application |
| Volvo Penta | AQ170A/B/C | 831040 | 130°F (54°C) | Marine stern-drive/out-drive application |
| Volvo Penta | BB165 | 875791 | 130°F (54°C) | Marine stern-drive/out-drive application |
| Volvo Penta | BB170 | 831040 | 130°F (54°C) | Marine stern-drive/out-drive application |
Technical Specs
- Product Type
- Replacement thermostat
- Installation
- Replacement installation in the original thermostat housing
- Application
- Volvo Penta stern-drive and out-drive marine engines
- Opening Temperature
- 130°F (54°C)
- Compatible Models
- AQ165A, AQ170A/B/C, BB165 and BB170
- OEM References
- 875791 and 831040
- Aftermarket Reference
- Sierra 18-3663
What’s in the Box
- 1 x replacement thermostat
A gasket, sealant and additional thermostat-housing hardware are not specified as included. Obtain any required gasket or sealing components separately according to the engine service manual.
Installation Notes
- Disconnect the vessel's battery and allow the engine to cool completely.
- Close the raw-water seacock if required by the engine's cooling-system configuration.
- Drain coolant or cooling water to a level below the thermostat housing as directed by the service manual.
- Remove the thermostat housing cover and note the orientation of the existing thermostat.
- Remove the old thermostat and clean the housing and mating surfaces without damaging them.
- Install the replacement thermostat in the same orientation as the original component.
- Install the required gasket or seal in accordance with the engine service manual. The gasket is not specified as part of this product.
- Reinstall the thermostat housing cover and tighten the fasteners to the manufacturer's specified torque.
- Restore the cooling system, reopen the seacock where applicable and check the engine for leaks.
- Start the engine, allow it to reach operating temperature and verify stable temperature operation.
Troubleshooting & FAQ
How do I verify this thermostat fits my engine?
Confirm that your engine is a Volvo Penta AQ165A, AQ170A/B/C, BB165 or BB170 and that the original thermostat corresponds to reference 875791 or 831040. Also verify the 130°F (54°C) opening temperature and compare the physical design with the thermostat being replaced.
What are the signs of a failing thermostat?
Common symptoms include engine overheating if the thermostat remains closed, slow warm-up if it remains open, unstable temperature readings or temperature changes during operation. Check the cooling system and water flow before replacing the thermostat.
What temperature does this thermostat operate at?
This thermostat is specified to begin opening at approximately 130°F (54°C).
Is this a complete thermostat kit?
No. The company product record identifies this item as a single thermostat. A gasket and other installation components are not specified as included.
Is a gasket included?
A gasket is not specified as included. Check the engine service manual and obtain the correct gasket or sealing component separately if required.
Is this an OEM Volvo Penta part?
This listing is for an aftermarket replacement thermostat. Volvo Penta part numbers 875791 and 831040 are provided only as product-identification references.
How often should a marine thermostat be replaced?
Replacement intervals depend on operating hours, water conditions and the engine manufacturer's maintenance schedule. Inspect the thermostat whenever the engine shows abnormal temperature behavior and follow the service manual for preventive maintenance.
How fast is shipping and what does it cost?
Available shipping methods, delivery estimates and costs are shown at checkout and depend on the destination and selected service.
Safety & Important Info
- Verify the engine model, original reference number, opening temperature and physical design before ordering.
- Do not operate the engine with an incorrectly installed thermostat or a leaking thermostat housing.
- Allow the engine to cool before opening the cooling system.
- Use the engine service manual for coolant handling, gasket requirements, fastener torque and final testing.
- This is an aftermarket replacement. Brand names and part numbers are used for identification and reference.
- Professional installation is recommended if you are not familiar with marine engine cooling systems.
About Sea Sierra
- Marine Parts Selection — We supply replacement components for a range of marine engine applications.
- Application-Focused Information — Product references and compatibility details are provided to help you compare the replacement with the original part.
- Global Fulfillment — Available shipping options and delivery estimates are presented at checkout.
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