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I bought a 81 project 4 speed and going through hoses and lines and found this line cut to this diaphragm looking module. Car has headers and edelbrock carb and rest is bone stock. Cut vacuum line goes into the two line grommet near the center of the firewall. I have Haynes manual but there’s no description for this part. On the side note, I’m really not liking edelbrock. After few days of sitting, float needle sticks and hard time starting the car unless I tap the top of each side with screw driver handle to loosen the float needle back down and carb is pretty much new. Car does not have fuel pressure regulator and has stock fuel pump. Could too much fuel pressure cause this?
Last edited by riverwabbit703; Aug 19, 2024 at 08:36 PM.
Looks like heater control valve on passenger side. Turns off hot water to heater core when AC engaged.
Edelbrock requires 5.5 psi not more than 6 psi. Could be too much from stock pump.
Thanks to both of you for great into. I don’t understand why people would cut this line in case someone down the line wants functioning AC. I was little thrown off about the dip stick on passenger side as well. I will try to reconnect this hose and get a fuel pressure regulator as I heard edelbrock says 6 mazpx psi and I believe stock 81 pump is 7,5 psi to 9 psi which may cause flooding.
Thanks to both of you for great into. I don’t understand why people would cut this line in case someone down the line wants functioning AC. I was little thrown off about the dip stick on passenger side as well. I will try to reconnect this hose and get a fuel pressure regulator as I heard edelbrock says 6 mazpx psi and I believe stock 81 pump is 7,5 psi to 9 psi which may cause flooding.
agree to hook it back up. it is supposed to close when the slider is moved to cold. There is a switch above glove box.
here is my 79 and detail of valve as well as adding shut offs as many do.. https://www.corvetteforum.com/forums...79-w-ac-2.html
While I was trying to hook the cut vacuum line to firewall grommet, one on the right is cut as well… I found the vacuum line that was cut and that comes off T fitting from headline vacuum line… more problems to solve. Really love the stance and look on this. Hopefully get her on the road soon.
Anyone know what this is?
