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Can anyone help me identify and understand this part? It is located directly below the EFE actuator on the passenger side.
What is the purpose of this part and what should the rubber line connect to? It's not connected to anything and has something inserted in the open end of the tube.
hot water shut off valve (vacuum operated)
Put vacuum on valve engine coolent does not flow thru heater core so air conditioning works better
Thank you for the feedback. I'm not clear on the recommended solution you proposed. Does the hose appear to be the correct length? I didn't see anything that I could connect it to, but maybe I missed it.
My AC does not work. Could this be related to the AC not working, or more likely unrelated?
2025 C2 of the Year ('64-'66) Finalist - Unmodified
2025 C3 of the Year Finalist - Modified
2025 C4 of the Year Finalist - Modified
2024 C4 of the Year Finalist - Modified
2023 C2 of the Year Finalist - Unmodified
2023 C4 of the Year Finalist- Modified
2022 C4 of the Year Finalist - Modified
2022 C3 of the Year Finalist - Modified
2021 C7 of the Year Winner -- Modified
2020 C4 of the Year Finalist - Modified
Originally Posted by mspmatt
Thank you for the feedback. I'm not clear on the recommended solution you proposed. Does the hose appear to be the correct length? I didn't see anything that I could connect it to, but maybe I missed it.
My AC does not work. Could this be related to the AC not working, or more likely unrelated?
Thanks again. Matt
not up on the correct plumbing for the vacuum line on a '77 but it needs to vaccum supply that comes from the heater control switch, somebody should be by with more help
That line starts at the Hot Water Shutoff Vacuum Switch.
There is a rubber grommet on the firewall the poly line ran through.
You will need to remove the shielding to see it, it is in the area where the white X is on this photo.
If you can find a stub of the white or yellow white poly line you can jet a length of 1/8" ID rubber vacuum hose to fit over the poly.
Just get a length of hose long enough to reach valve.
That is why you see a white hose inside the rubber hose your holding, a repair was made at the valve.
That line starts at the Hot Water Shutoff Vacuum Switch.
There is a rubber grommet on the firewall the poly line ran through.
You will need to remove the shielding to see it, it is in the area where the white X is on this photo.
If you can find a stub of the white or yellow white poly line you can jet a length of 1/8" ID rubber vacuum hose to fit over the poly.
Just get a length of hose long enough to reach valve.
That is why you see a white hose inside the rubber hose your holding, a repair was made at the valve.
Thank you. Your photo helps a lot. Appreciate you taking the time to post it.
Thank you for the feedback. I'm not clear on the recommended solution you proposed. Does the hose appear to be the correct length? I didn't see anything that I could connect it to, but maybe I missed it. My AC does not work. Could this be related to the AC not working, or more likely unrelated?
Thanks again. Matt
Simple answer is NO.
Both A/C and NON A/C cars had the hot water shut off valve, but they were in different locations.
On the HVAC control Panel...
The upper slider lever controls the electrical switching and is interlocked with the 5 port vacuum switch of your heater controls.
The Lower slider lever is connected via cable going to the top of your cabin side heater box.
The Hot Water Shutoff Vacuum switch is there.
Thanks again everyone for your help. Turns out the poly line was still in tact, but the open end was hiding under the top of the fender. All I had to do was route it back down and connect it to the nipple on the valve. Looked like maybe it had just become brittle and broke off.
That line starts at the Hot Water Shutoff Vacuum Switch.
There is a rubber grommet on the firewall the poly line ran through.
You will need to remove the shielding to see it, it is in the area where the white X is on this photo.
If you can find a stub of the white or yellow white poly line you can jet a length of 1/8" ID rubber vacuum hose to fit over the poly.
Just get a length of hose long enough to reach valve.
That is why you see a white hose inside the rubber hose your holding, a repair was made at the valve.
Part identification - 1977 L48 automatic
