The butterfly on the intake horn should be connected by a hose to a temperature operated valve in the center of the top of the cleaner. The other fitting on the top runs to a vacuum port on the manifold. For this to do anything useful, there's also a large paper hose from the underside of the intake horn to a port on the rear sheet metal, that allows hot air off the cylinders into the hose. If this hose is gone, there's no hot air into the air cleaner and the sensor will not get hot enough to operate. On a hot day it might keep the butterfly open all the time, and on a cold day it would never open.
If you run the hose from the manifold directly to the butterfly operator, it should open when the engine is running. If not, it's jammed or the diaphragm in the operator is damaged - or you've got no vacuum. That's the first thing to check - is the hose from the manifold pulling a good vacuum. Chuck Kuecker Damon & Gay wrote: > Dear Fellow Subscribers, > Hello, > I own a 1972 VW Beetle, 1600 engine, all original. I have a question about > the oil bath air cleaner. > There is a vacumn controled device on the air flow tube that has a butterfly > that closes the flow of air when the engine is running. Is the butterfly > supposed to open up the air supply after the engine is warm? Mine does not > open no matter what the temp. > > Thanks, > Bluebeard. > _______________________________________________ > vintagvw site list > [email protected] > http://lists.sjsu.edu/mailman/listinfo/vintagvw > > > _______________________________________________ vintagvw site list [email protected] http://lists.sjsu.edu/mailman/listinfo/vintagvw
