I have a 77 with no AC. I get constant low speed hot air coming in the heater vents. No matter how I set the dials, I get it. There was a post on another website by Ganey that talked about pulling the brown wirethat leads to the heater/AC box on the outer firewall. Since I don't have AC, I only have a red and black wire leading to it. Does anyone know of a way - easy way to disconnect the low speed but have the rest of the system work if need be.
Thanks, Bob :cheers: :cheers:

 

Even if you kill the blower, you'll still have hot water flowing through your heater core which is the real problem. Suggest you splice in a manual cutoff in your heater supply line to rectify the problem and still have airflow.

 

My 77 had this problem as I'm sure all do or did. I disconnected the heater hoses from the heater and looped a tube from the manifold to the water pump. Florida is my heater. I insulated the floor with a heat barrier and also put in a new foam cushion around the top of the bellhousing. I did the fan cutoff by unplugging the connector that sits atop where the blower unit is and bent over one of the tabs to stop it. Mine was the one tab that is closest to the fender or the outside one if that makes any sense. Think of the connector as a T and the tab at the bottom of the T is the hot wire for the fan. The fan still works by switch it just dosn't come on when key is turned on. That made the biggest difference so far. You may have to go through a process of elimination to find the right wire. Just unplug one at a time until you find it. You can also stuff foam rubber chunks into the out lets by your feet (both sides to prevent any other seepage) (Bubba fix). Insulation is important as the heat from the engine compartment comes right through the firewall. I can feel the hood release emminating heat after a 1 hour spin. A/c would eliminate all heat at the feet and is the ultimate fix. Also the exhaust pipe heat that runs under you contributes to the problem. I'm going with ceramic headers soon and hope this eliminates some of the heat. I even thought about wrapping the exhaust pipes with header wrap but I think this may be a detrimental to exhaust dynamics? :reddevil