Hello from the UK,

I am new to the forum and this is my first post. In May 2009 I rescued a MB 1972 350sl from a field...it's a long story!!!

Its up and running well now but as the winter has arrived I found the heater doesn't work.

The problem seems to be the vacuum system that activates the heater valve that allows the hot engine water to flow into the heater box. If you look at the picture you will see a black pipe with a blue check valve...can anyone tell me where that connects to....is it on the manifold or, some where else?

Bear in mind that this car is the European early model and has just the basic heater and no Air Con.