Thermostat 55C 875791 for Volvo Penta AQ165 AQ170 BB165 BB170 Gasoline
Thermostat 55C 875791 for Volvo Penta AQ165 AQ170 BB165 BB170 Gasoline
Product Overview
Thermostat for Volvo Penta AQ and BB marine gasoline engines, opening at 55 °C (131 °F) and supplied as 1 x thermostat. It replaces Volvo Penta 875791 and 831040, and crosses to Sierra 18-3663. These AQ165 and AQ170 engines are raw water cooled and run a cold thermostat on purpose, so the engine reaches operating temperature quickly without thermal shock on the cast iron; fitting a hotter automotive thermostat is what causes the corrosion and cracking these blocks are known for. A thermostat stuck open keeps the engine cold, which shows up as rough running and excess fuel use, while one stuck shut overheats the manifold within minutes.
Specifications & Attributes
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Thermostat |
| Engine | Volvo Penta AQ and BB marine gasoline |
| Opening Temperature | 55 °C (131 °F) |
| Models | AQ165A, AQ170A-C, BB165A, BB170A-C |
| Quantity | 1 thermostat |
| Shipping Weight | 123 g |
| Packaging Size | 150 x 100 x 50 mm (5.9 x 3.9 x 2.0 in) |
OEM Cross Reference
| Brand | OEM Part Numbers |
|---|---|
| Volvo Penta | 875791 |
| Volvo Penta | 831040 |
| Sierra | 18-3663 |
Compatible Engines
| Engine | Type | Opening Temperature |
|---|---|---|
| AQ165A | Marine gasoline | 55 °C (131 °F) |
| AQ170A | Marine gasoline | 55 °C (131 °F) |
| AQ170B | Marine gasoline | 55 °C (131 °F) |
| AQ170C | Marine gasoline | 55 °C (131 °F) |
| BB165A | Marine gasoline | 55 °C (131 °F) |
| BB170A | Marine gasoline | 55 °C (131 °F) |
| BB170B | Marine gasoline | 55 °C (131 °F) |
| BB170C | Marine gasoline | 55 °C (131 °F) |
What's Included
| Component | Qty |
|---|---|
| Thermostat 55 °C | 1 |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | Standard |
| Packaging | Sealed retail packaging |
Before You Buy
- Check the engine model plate, AQ165 and AQ170 use a 55 °C thermostat and a hotter one will change how the block warms
- Test the thermostat in a pan of water before fitting, it should start to open at 55 °C
- Renew the housing gasket, it is not in the box
- Check the old thermostat for a broken bridge or a pellet pushed out, both mean it has failed open
- Refill with the correct coolant mix and bleed the raw water side before the first run
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Before You Buy
Frequently Asked Questions
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