1976 Firewall Vacuum
Thread Starter
Burning Brakes
Joined: Sep 2002
Posts: 1,009
Likes: 62
From: Houston Tx
1976 Firewall Vacuum
Hi all, can anyone tell me where this vacuum in the picture connects under the hood? It's coming in from the firewall on the passenger side of the distributor. It's the one on the top toward the right in picture with the yellow arrow that I am trying to find out what it connects. Thanks.
Here is a vacuum diagram pic from my '77.....maybe the '76 is similar....something to work with anyhow
Thread Starter
Burning Brakes
Joined: Sep 2002
Posts: 1,009
Likes: 62
From: Houston Tx
Ok, thanks. I think this may be why I am not getting much air flow through the side air vents when I turn the A/C on. I can hear the blower blowing just can't get any air flowing.
Safety Car
Joined: Mar 2007
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Should be white or light yellow. Should run to a valve on the heater hose. It is supposed to shut off water going to the heater core when A/C is on. If it is cracked or not connected it ends up being a vacuum leak making the other vacuum not work well in the system and not letting other valves close or open like they should.
Top left in that drawing.
Be sure it is connected or block it off.
Top left in that drawing.
Be sure it is connected or block it off.
Thread Starter
Burning Brakes
Joined: Sep 2002
Posts: 1,009
Likes: 62
From: Houston Tx
Hi all, can anyone tell me where this vacuum in the picture connects under the hood? It's coming in from the firewall on the passenger side of the distributor. It's the one on the top toward the right in picture with the yellow arrow that I am trying to find out what it connects. Thanks.
Race Director
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From: Sunshine Coast, Queensland, Australia
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Do you have your dash apart? If not remove the right hand side. And perhaps the dash top. (A Piller trim on the right will need to come out). Now you can access the switch that sends vacuum to the water shut off valve. If you still have a water shut off valve. Connect a new line at the switch. (See diagram a couple posts up). Run new line threw grommet and out to water shut off valve. A section of tubing ground sharp makes a good hole drill to drill through rubber grommet. Reseal with silicone.
if you don't have a water shut off valve or heater core for that matter. Back up further and plug line to the switch.
if you don't have a water shut off valve or heater core for that matter. Back up further and plug line to the switch.
Thread Starter
Burning Brakes
Joined: Sep 2002
Posts: 1,009
Likes: 62
From: Houston Tx
Ok, thanks 4-vettes; Dash is pretty much still apart. I put a new AC harness in and have not put the Center console back in yet. I think I can manage with that. Where do you find that kind of line? I'm thinking of just using some rubber wiper washer hose or will that be to thick? Thanks.
Last edited by hgoodwiniii; Nov 3, 2020 at 07:50 AM.
