Since I have had my car, the defrost has been on constantly. During the winter, its a welcome "problem" but now its getting too hot around here for this.

I read up on the heating system and think I got the jist of it, and know mine is not working correctly. First off, I wanted to get the heat to stop from pouring into the cab.

I thought the flapper boxes were the only way for heat to get to the defrost, but after taking off both of them, they both work fine and are closed 100% of the time since the lever control wire is too lose (I'll fix that later).

The point is if the flapper boxes are closed, how there heat coming into the cab all the time??

Also, does the lever for early cars (mine is a '72) ground the blower motor? Mine was missing the fuse for the first couple months, and once I put it in, it ran anytime the iginition was turned on. I took out the fuse because I was trying to listen to the fuel pump, but once I put the fuse back in, the blower is not turning on. I do not remember what position the lever was in when the blower motor was working because I did not know it grounded the blower (if it does).

Next question I have is are the flapper boxes the same for both sides of the car, just mounted opposite of each other? I got the one on the drivers side off no problem, but on the passenger side, the bolts face up towards the engine and are a pain to get to! I knew it worked ok by taking off one of the hoses and feeling with my finger while opening and closing it.

Thanks guys!

with the valve control wire disconnected the heat is still on? with the wire off, the valve to body flex lines off @ the valve side, car jacked up and running see if hot air is coming out of the valve. you might have to rev it up a bit to get the air volume up.

on my car both of the valve control arms are on what i consider the top portion of the valve with the arms to the centerline of the engine. you may have 2 of the same side.

the aux heating fan should only activate when the console lever is pulled fully up. sounds like the ground is being provided all the time. the green wire/tab may be making contact to metal, or the switch is faulty, or the fan itself may have been wired direct.

work your way back to from the control lever.

k

The flapper valve is metal with a rubber type washer all the way around the edge...Its gone now...ages does that.

Start simple. Remove the nose going from the flapper box to the chassis.
Cover the hole in the chassis on both sides so the vacuum affect that your roofless car creates is not going to suck air in from those chassis holes.

Now you should have no heat.
The mixer valve in front, just under the windshield on both sides of the car is where the defrost enters the vehicle...guess what...it also has the same gasket..and its also gone at this age.

You also have a fresh air hose that goes to the fresh air box in the front of the car, this is poor mans AC...the levers and cables may be either stuck, or wired up wrong.
Watch the mixer valve while someone moves the top most heater control lever full left (off) to full right(on) and watch both mixer valves under the windshield. They should do the same thing. They should flip over the valve to full cold air and should go in the same direction.

Rich