Author Topic: 1978 vacuum selector switch  (Read 3816 times)

Offline pwunderlich

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1978 vacuum selector switch
« on: May 15, 2011, 09:18:38 AM »
Hey guys...my a/c selector is shot and I am having a heck of a time finding a replacement.  It sits on top of the a/c control box and has a bunch of vacuum lines going to it.  I figure its shot b/c when you turn on the a/c the air blows out of all the vents at once no matter where you put the switch.  Even the specialty shops can't help me and i literally live down the road from outback.  >:(
Thanks guys
Pat

Offline VileZambonie

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Re: 1978 vacuum selector switch
« Reply #1 on: May 15, 2011, 09:22:03 AM »
What is outback? Are you just assuming it's shot or have you tested it? You are referring to the switch in the dash?
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Offline zieg85

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Re: 1978 vacuum selector switch
« Reply #2 on: May 15, 2011, 09:22:27 AM »
Make sure you have vacuum going to it.  There should be a black vacuum container about the size of a small grapefruit mounted on the firewall.  Engine vacuum goes into it and then a small line goes through the firewall to operate the vent/selectors of the HVAC system.
Carl 
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1986 C10 under construction
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Offline pwunderlich

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Re: 1978 vacuum selector switch
« Reply #3 on: May 15, 2011, 10:04:09 AM »
What is outback? Are you just assuming it's shot or have you tested it? You are referring to the switch in the dash?
this place http://www.outbacktruckparts.com/  I get alot of stuff from here.

Im gonna try Zieg85's idea.  I was assuming its shot b/c it didnt look too good, but I'll give it a try.
but in case it is bad...anyone know where to find one?  I know some other people that do need the same part also
thanks guys
« Last Edit: May 15, 2011, 10:07:17 AM by pwunderlich »

Offline VileZambonie

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Re: 1978 vacuum selector switch
« Reply #4 on: May 15, 2011, 10:13:54 AM »
Yea you should start testing it before you start throwing parts at it. Make sure like Zeig said - #1 you have vacuum to the reservoir and #2 that the vacuum hoses are both connected.
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10