No announcement yet.

Vacuum Connection at Intake


Unconfigured Ad Widget

  • Filter
  • Time
  • Show
Clear All
new posts

  • Vacuum Connection at Intake

    Hi! I have a 1983 C30 with a 454, A/C, Cruise Control, and Hydroboost brake system. When I got the truck, about a year ago, I found it had major issues with the vacuum lines. I was able to correct the emissions vacuum issues, but I still have a couple issues hanging.

    The Intake Manifold Vacuum Fitting (between the carburetor and distributor) has three
    1/4 inch ports.
    One goes to the transmission.
    Another goes through a Vacuum Delay Valve to the Vacuum
    Reservoir. Out the bottom of the Delay Vlv. are two ports;
    one goes to the Cruise Cont. and the other port is plugged
    with a bolt. I'd like to know where this plugged line is supposed to be connected.
    The third port is connected to the Windshield wiper pump. Now I know that line is
    actually supposed to go to the Windshield Wiper Fluid Reservoir. But what is really
    supposed to be connected to this vac. fitting port?

    And finally; the image below shows a spherical device on the passenger side. I have no
    idea what this is. There is a vacuum line running out of it, but it has been cut and
    plugged. The vacuum line can also be seen in the photo. Can anyone please tell me what
    this thing is and where it connects?

    I appreciate any help you can offer me.

    Last edited by 83C30; 12-24-2009, 10:22 PM.

  • #2
    Re: Vacuum Connection at Intake

    do your heater vents move between floor/vent/defrost?
    ASE Master Certified Technician

    2000 Silverado 6.0 4L80E 2wd
    *RIP*1994 Z71 SCLB 355, Dart Heads, 10.5:1 CR, PM rods, CC XR270HR


    • #3
      Re: Vacuum Connection at Intake

      That's been all disconnected. The guy who had it before me ripped
      everything apart to replace the heater core. He never completed
      the work. And now I have a pile of parts, from under the dash, to
      put back together.


      • #4
        Re: Vacuum Connection at Intake

        Anyone? Anything?


        • #5
          Re: Vacuum Connection at Intake

          Originally posted by 83C30 View Post
          Anyone? Anything?
          The vacuum ball has a vacuum hose that goes to the heater and the large hose goes to the vacuum manifold fitting. The hose from the HVAC is about 1/8" and usually clear or white with a black adapter end.
          04 K1500 Silverado EXT 3:73 gears, 5.3L 265/75-16,Pace Edwards tonneau,


          • #6
            Re: Vacuum Connection at Intake

            Thanks for your reply. I thought I'd hit a wall here, but now you've got me moving forward again.