Date registered: Jul 2011
Vehicle: 1993 600SL, 1973 450 SL,1982 380SL,1998 SLK 230, 1968 Firebird, 2001 Dodge Ram 4x4,2005 Ford Escape
Location: washougal Wa
Mentioned: 7 Post(s)
Quoted: 414 Post(s)
Your original thought was correct, they bring in outside air. Rowdie just posted a link to the 107 maintenance manual to a guy that asked for it. Go to that link, punch in the 73 and look at the heating section. It has diagrams of the vacuum system. From that you should get a good idea how it all works. Glad to know the attachment wasn't rusted off or something. That was the idea behind you checking that. The fact that you pull it up with some resistance, then it goes back down indicates to me that the pod is holding vacuum on one side at least. Seems like it isn't getting vacuum to the side that holds it open. I'd check the connections at the dash switch, then work your way up. I tried to apply vacuum to my car as the vents are exposed, but I have too many lines unhooked to make the vac system work. Also, I may have an issue at my rotory switch, as it seems to want to twist in a circle instead of stopping one direction then the other. I don't think your problem is major. Be sure you clean out the drain hole while you have the covers off. Its in the lower front corner. The water fills up that area and runs over the dam into the heater box, then onto the floors. Perhaps your problem. Good luck !
Last edited by tdoriot; 04-29-2012 at 08:54 PM.