Thermostat Cable - Type 4 Engines (Shorten To 350mm For T25 1600cc CT Engine)

This replacement thermostat cable is used to connect the engine thermostat to the cooling flaps inside the engine tinware on Volkswagen aircooled engines. It is fitted as standard on all VW Baywindow Buses equipped with Type 4 aircooled engines in 1700cc, 1800cc, and 2000cc configurations, and is also used on early Type 25 (T3) Buses with 2000cc aircooled engines.

The thermostat system on aircooled Volkswagen engines is designed to regulate engine temperature during warm-up and normal operation. When the engine is cold, the thermostat contracts and pulls on this cable, keeping the cooling flaps closed to restrict airflow. This allows the engine to warm up quickly, reducing internal wear and improving oil circulation. As the engine reaches operating temperature, the thermostat expands, relaxing the cable and allowing the cooling flaps to open fully so cooling air can flow over the cylinders and heads.

If the thermostat cable is missing, stretched, seized, or broken, the cooling flaps may not operate correctly. This can result in slow warm-up, increased engine wear, uneven cooling, or in some cases flaps remaining permanently open or closed. Replacing the cable restores correct operation of the thermostat and cooling flap system, helping to protect the engine and maintain stable operating temperatures.

This is a top-quality replacement cable, manufactured to the correct length and specification for Type 4 engines. It measures 469mm overall and installs directly in place of the original.

The cable can also be used on VW Type 25 models fitted with the 1600cc CT aircooled engine, but in this application it must be shortened to 350mm before installation.

Other parts that may be required or worth checking when fitting:

• Thermostat

• Cooling flaps (left and right)

• Return springs

• Thermostat bracket and mounting hardware

Ensuring the thermostat cable is correctly fitted and adjusted is essential for proper engine warm-up, efficient cooling, and long-term reliability.

Measurements

• Length: 469mm

• Note: Shorten to 350mm for 1600cc CT aircooled engines

Applications

• VW Baywindow Van: 1968 – 1979 (Type 4 aircooled engines)

• VW Type 25 / T3: 1979 – 1985 (aircooled engines)

• Porsche 914: 1970 – 1976

Compatible Aircooled Engine Codes:
CA, CB, EA, W (1700cc)
AW, AP, ED (1800cc)
CJ, CU, CV, GD, GE (2000cc)
CT (1600cc aircooled – requires shortening)