23172729 Thermostat | Genuine Volvo Penta Part

🔧 Product Description

Genuine Volvo Penta thermostat from the Cooling System group, weighing 0.077 kg and listed for eight D series engine applications. It supersedes part number 23059851. A thermostat stuck open runs the engine cold; stuck closed it overheats.

🚤 Compatibility

Typically suits:

• Volvo Penta D8A2-A MP
• Volvo Penta D8A5-A MH
• Volvo Penta D8A6-A MH
• Volvo Penta D8A5-A MG
• Volvo Penta D8A6-A MG
• Volvo Penta D8A4-A MP
• Volvo Penta D8A1-A MP
• Volvo Penta D8A3-A MP

• Engine Family: D

⚙️ Key Features

• 0.077 kg
• Listed for eight D series engine applications
• Supersedes 23059851
• From the Cooling System group

🔌 Function

Holds coolant flow back until the engine reaches operating temperature, then opens to let it pass to the cooler.

⚠️ Common Signs of Failure

• Engine slow to warm up or never reaching normal temperature
• Overheating that comes on quickly with the top hose staying cold
• Temperature gauge swinging up and down instead of holding steady
• Valve found seized part open, or corroded and furred on removal
• Coolant weeping at the housing joint

🛠️ Service Notes

• Renew the seal or gasket with the thermostat rather than reusing it
• Test the old unit in hot water before assuming it was the fault - a blocked cooler or a failing pump gives the same overheating
• Where the engine takes a pair, renew both together so the two open at the same point

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 23172729 → Supersedes 23059851 → Supersedes 22333526

OEM / Related Numbers

• 23059851 earlier number superseded by this part
• 22333526 earlier number superseded by this part

📦 Condition

• Genuine Volvo Penta part
• Brand new
• Supplied in original or equivalent packaging