Cornfused!!!!!!!!!
Thread Starter
Melting Slicks
Joined: Aug 2013
Posts: 2,178
Likes: 111
From: Plains Pa
Cornfused!!!!!!!!!
Please help with this problem....I have a 75 with air and bought a new heater control valve but can't find the white vac line that connects to it.....it has to come out of the firewall somewhere! Thanks in advance!
Pro
Joined: Nov 2011
Posts: 517
Likes: 20
From: Scroggins Tx
My 75 has two tubes coming thru the firewall and neither is white. The solid black on the upper left connects to a vacuum source either on the manifold or carb. The one on the lower right connects to one with a green stripe and goes back thru the firewall into the wiper area and connects to a fresh air door. As you can see both of mine have been spliced due to hungry rats.
Drifting
Joined: Aug 2005
Posts: 1,443
Likes: 65
From: Wauconda IL
From what I've been able to determine, the HW valves were installed from 68-70 and then re-appeared in 76.
I don't think 72-75 had them (not sure about 71) so you won't find the white hose. What confuses things is that most parts vendors sell valves for all these years even though AIM and the shop manuals don't show them installed or the white hose for them.
I don't think 72-75 had them (not sure about 71) so you won't find the white hose. What confuses things is that most parts vendors sell valves for all these years even though AIM and the shop manuals don't show them installed or the white hose for them.
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Drifting
Joined: Aug 2005
Posts: 1,443
Likes: 65
From: Wauconda IL
Did you have one originally on your car?
If so, it should have had the hose connected?
If you have a valve and no sign of a hose, it sounds like someone may have installed one previously and realized there was no hose either-
In any case, the valve is worthless without the vacuum source as it will always remain open.
What you could do is tap into the (green) line that goes to the plenum valve in the cowl and that way, the valve would close anytime the A/C was set to 'MAX' or 'Recirculate', which is essentially all the white hose does anyway.
If so, it should have had the hose connected?
If you have a valve and no sign of a hose, it sounds like someone may have installed one previously and realized there was no hose either-
In any case, the valve is worthless without the vacuum source as it will always remain open.
What you could do is tap into the (green) line that goes to the plenum valve in the cowl and that way, the valve would close anytime the A/C was set to 'MAX' or 'Recirculate', which is essentially all the white hose does anyway.
Racer
Joined: Aug 2005
Posts: 456
Likes: 0
From: Forty Fort PA
Guess I didn't pay enough attention to the original post. My 75 did not originally have a water shut off valve connected to the a/c system. I added the valve and installed a second vacuum valve like the one used for the headlights under the dash, ran a hose out through the grommet to connect to the valve. Since I installed the water shut off, I have only opened it once.
langg
langg
Thread Starter
Melting Slicks
Joined: Aug 2013
Posts: 2,178
Likes: 111
From: Plains Pa
The fellow who had the car before me had a manual shut off in between the heater hoses I thought the original was broken and he replaced it with that one. I can't believe they changed things around for a few years and went back to the original setup. The person who sold the heater valve to me said it was the correct one for the car.....now I'm wondering..................
Burning Brakes
Joined: Apr 2010
Posts: 1,018
Likes: 9
From: Winston Ga.
my 75 had a vac valve in it too. I swapped for a manual one. My vac lines are not color coded either.
is yours black plastic with two hose connections and a vac connection on top? thats mine.
is yours black plastic with two hose connections and a vac connection on top? thats mine.
BTW, Ted Nugent rocks!!!!!
