Thermostatic vacuum switch in air filter box
I've bought three new A/C vacuum switches and I cannot get it to close when the engine is cold to open the flapper valve to route the intake air over the exhaust. Has anyone had success getting this to work? When I connect the vacuum port on the manifold directly to the flapper it opens it as it should. But whether hot or cold the vacuum switch in the air filter box does not allow the vacuum to pass through - it just leaks out. Help!


This is a Type C engine in a 1956 XK 140. At present it doesn’t appear the engine needs more than a tune-up and some care. I would like to get it out of the car and clean, repaint and polish what can be done. As an aside, while it’s out of the car I’d like get the car repainted, new interior and new top.