Anybody know where I can get a replacement vacuum adapter for my 72 gs? It is a three pronged dealy bop that attaches at the intake and goes to the butterfly valve in the air cleaner. Mine broke and the dealership is useless. Any ideas would be appreciated. Thanks. Goof
I know what you are referring to. Try Year One and Orig. Parts Group. I'll look a little harder later, but am certain that you can find that part.
Doug, Are you doing a concourse restoration on the car? If not, you really don't need the ported vacuum switch. It is part of the transmission controlled spark advance. It eliminates vacuum advance in 1st and 2nd gear, and then allows it in 3rd. It also applies full manifold vacuum to the distributor if the engine temperature should climb above 220*, cooling it down. You can run manifold vacuum directly to the temp sensor in the air cleaner and run a direct line from the ported nipple on the carb to the vacuum advance can at the distributor. This way you have full time vacuum advance and your air cleaner door works as before. Use the hole in the manifold for a temperature gauge sender or plug it up.
Evans, There are two ports on the average Q-jet. The drivers side is ported vacuum, the passenger side full manifold vacuum. The air cleaner door works off a temperature sensor located in the air cleaner base. It requires full manifold vacuum to work. The sensor has two connections from it's bottom side. One side gets full manifold vacuum, the other side goes to the vacuum motor(door) in the snorkel. The sensor modulates vacuum to the vacuum motor which keeps the door in the correct position to maintain air temperature in the air cleaner housing. Your spark advance can be ported or manifold, your preference. If full manifold advance, just tee into the line going to the temp sensor. Here's a picture from the 70 Chassis manual. I colored the full manifold path to the air cleaner red.
It's called a 1970 Buick Chassis Service Manual. They should be available on CD Rom, or advertise in the Parts wanted forum. Someone may sell you one.
