Where to locate the thermostat in an 1985 VW golf?
The thermostat is located at the bottom of the water pump. Follow the lower radiator hose to the water pump and you will see it connects to the water pump outlet (molded plastic/cast alloy depending on year). The outlet is secured by two 10mm bolts. The thermostat sits inside the outlet. Have a fresh O-ring handy in case the old one is perished (a decent thermostat kit should come with O-rings).