Oil thermostat. Porsche 911S  ❭  90110780101

Oil thermostat. 

High quality OE Match oil thermostat designed to regulate engine oil temperature on classic Porsche 911 S models. This precision thermal valve opens and closes based on oil temperature, helping your engine reach and maintain optimal operating temperature quickly and reliably. It is engineered as a direct fit replacement for the original Porsche thermostat, ensuring correct function and reliability.

Fits:
Porsche 911S - 1969 to 1971

Diagram ref no 12

What This Product Does:
The oil thermostat helps the engine reach and maintain its optimal oil temperature by restricting or allowing oil flow to the oil cooler:

• Cold start: Restricts oil flow to allow faster warm-up
• Normal operation: Opens progressively to route oil to the oil cooler
• Temperature regulation: Keeps oil in the correct operating range for lubrication and longevity

This ensures the engine oil warms efficiently and stays within the temperature range where it provides superior lubrication, reduced wear, and proper viscosity for all operating conditions.

Why Replacement Matters:
The oil thermostat plays a crucial role in thermal management for air-cooled Porsche engines.
Over time, thermostats can stick, corrode, or fail, which can cause:

• Prolonged cold oil conditions on start-up, leading to accelerated engine wear
• Excessive oil cooling once warm, reducing engine efficiency
• Fluctuating oil temperatures and unstable operating conditions

Replacing a worn or failed thermostat restores accurate oil temperature control, improves engine warm-up behaviour, and helps maintain proper lubrication and performance under varied driving conditions.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

90110780101

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