Does anyone else have excessive heat inside the car?
Went for a drive today and found there is a lot of Heat coming into the car, like the heater is blowing hot air into the cabin area.
The hood seal is fine so nothing getting into the cowl area.
I'm tempted to bypass the heater core to rule out a problem in the heater box or cables shutting down the heat flap from the box.
It is an a/c car.
Anyone have any ideas as to what could be causing it?
Big blocks are hot, but did you bypass the heater core? If not the water valve in engine compartment may have failed. This assumes the vacuum controls are hooked up correctly under the dash. My 68 had AC, and my 70 big block car does too. I hate under dash projects due to all the AC stuff.
Haven't bypassed the heater core yet but that's the first thing I will do to rule out a heater box or as you suggest the water valve in the engine bay.
Quote from: Rickmustang on January 28, 2020, 09:27:10 PM
Big blocks are hot, but did you bypass the heater core? If not the water valve in engine compartment may have failed. This assumes the vacuum controls are hooked up correctly under the dash. My 68 had AC, and my 70 big block car does too. I hate under dash projects due to all the AC stuff.
Probably not the heater hose valve. That valve only closes off the flow of water in the heater hose when the A/C is on. If the A/C is not on the water flows through the valve and through the heater core whether the heater is on or not . I suspect ether faulty vacuum or faulty duct function in the heater box.
Thanks Bob, if it is a faulty vacuum or duct function is there any way to check it without pulling out the heater box?
I once had a KR with similar issues. Make sure all the rubber plugs are intact on the firewall
Everyone has added something that may contribute to fixing your possible problem. Most of my cars are big block powered and some have the propensity to run angry hot if allowed to do so. Trouble shooting is an analytical process, start off with the heat source. Is the heat coming from the cabin or from the engine compartment, run a bypass hose on your engine eliminating any hot water from entering the cabin area. A simple loop to eliminate the heater hoses from going into the car, Drive it around and see if that fixes the problem. Does ANY heat seem to be coming in from the firewall area at least what might seem abnormal to you. Since its winter time it will be easy to feel, plug any firewall or floorboard holes allowing heat into the car. Move on down the line to any inside car items, heater core, valves, hoses, controls etc. you should be able to see or feel if hot air is coming from the plenum or somewhere else. Use all you senses and you will be able to decipher where your trouble is coming from. Good Luck! ;)
(Edited 2/2/2020 because Bob is right)
Bob the valve that ports vacuum to the hot water valve is closed unless the temp cable is moved to the lower position. So water only flows then. It does not matter if the fan switch is on or off. So the only time heat should come from the system is when the cable is moved down, which also opens the heat door. The hot water valves are spring loaded open. When they fail, they fail open. The heater core does get warm anyway just from the stagnant water eventually getting warm through contact. But it will not be as warm as it could be if the valve were open.
The fan switch controls the air conditioning compressor power, in combination with the icing switch. Turning the fan on will supply 12 volts to the fan clutch unless interrupted by an open icing switch.
If you are getting warm air in the cabin it is most likely the foam rubber in the heater / AC box is rotten and allowing air to get through / around the closed heat door.
Another possibility would be someone has purposely disconnected or plugged vacuum to the heater valve so it is open. You can check this easily by removing the vacuum hose from the top of it with the heat cable set to full cold. There should only be vacuum when the heat lever is at the top and the engine is running.
Quote from: Bob Gaines on January 28, 2020, 10:29:06 PM
Quote from: Rickmustang on January 28, 2020, 09:27:10 PM
Big blocks are hot, but did you bypass the heater core? If not the water valve in engine compartment may have failed. This assumes the vacuum controls are hooked up correctly under the dash. My 68 had AC, and my 70 big block car does too. I hate under dash projects due to all the AC stuff.
Probably not the heater hose valve. That valve only closes off the flow of water in the heater hose when the A/C is on. If the A/C is not on the water flows through the valve and through the heater core whether the heater is on or not . I suspect ether faulty vacuum or faulty duct function in the heater box.
Quote from: Royce Peterson on January 29, 2020, 11:11:45 AM
Bob the valve that ports vacuum to the hot water valve is closed unless the temp cable is moved to the lower position. So water only flows then. It does not matter if the fan switch is on or off. So the only time heat should come from the system is when the cable is moved down, which also opens the heat door. The hot water valves are spring loaded shut. When they fail, they fail shut. The heater core does get warm anyway just from the stagnant water eventually getting warm through contact. But it will not be as warm as it could be if the valve were open.
The fan switch controls the air conditioning compressor power, in combination with the icing switch. Turning the fan on will supply 12 volts to the fan clutch unless interrupted by an open icing switch.
If you are getting warm air in the cabin it is most likely the foam rubber in the heater / AC box is rotten and allowing air to get through / around the closed heat door.
Another possibility would be someone has purposely routed vacuum to the heater valve so it is open any time the engine is running. You can check this easily by removing the vacuum hose from the top of it. There should only be vacuum when the heat lever is at the bottom and the engine is running.
Quote from: Bob Gaines on January 28, 2020, 10:29:06 PM
Quote from: Rickmustang on January 28, 2020, 09:27:10 PM
Big blocks are hot, but did you bypass the heater core? If not the water valve in engine compartment may have failed. This assumes the vacuum controls are hooked up correctly under the dash. My 68 had AC, and my 70 big block car does too. I hate under dash projects due to all the AC stuff.
Probably not the heater hose valve. That valve only closes off the flow of water in the heater hose when the A/C is on. If the A/C is not on the water flows through the valve and through the heater core whether the heater is on or not . I suspect ether faulty vacuum or faulty duct function in the heater box.
Royce,I did not mention anything about a control in my post only the heater hose valve. If you think that the water valve on the heater hose is normally closed then you are misinformed . The valve closes when vacuum is applied . It snaps back open when that vacuum stops. It is designed so that if the A/C is on the flow of hot water is stopped so that the heater core is not fighting the evaporator core.
Guys, thanks for your suggestions.
As i mentioned in my initial post my first step will be to bypass the heater core to isolate heat in the heater box.
I'm in Australia, being summer and bushfire season here at the moment i've got a hot couple of days with temps expected to be around 110 deg Fahrenheit. Obviously I don't need extra heat in the car.
So I found a link which I included in this post and it gives a great view and description of what is going on with the Selectaire system.
I does mention the operation of the heater control valve
3. Electrical and vacuum functions are illustrated here. When you apply heat, you are moving the Bowden cable, which affects the heat control door and hot water valve function. The hot water valve is either on or off depending upon vacuum application. Each vacuum port at the vacuum regulator directs vacuum to the appropriate servo motor depending upon control position.
http://www.mustangandfords.com/how-to/interior-electrical/1601-troubleshooting-classic-mustang-climate-control
Can't road test today as it is bad and stormy weather in Melbourne so I've done just run it in my garage.
What I found so far is the vacuum is operating fine as it changes direction of air flow from screen to face to floor so the doors are operating.
However I found that in the off position on the 1 lever and with the cool setting on the centre lever of the control which runs the Bowden cable the fan running in all 3 speeds blows air into the floor area just like when it is in the heat position.
So I'm thinking that either the door doesn't fully close or the foam is deteriorated. The amount of air passing through is the same so I don't think it deteriorated foam with a closed door as the closed door should still reduce the air flow even if it allows some through.
The door actuator is moving all the way in and out when operating the Bowden cable to and from the heat position so its moving the door from open to closed, but is it closing all the way.
So I'm wondering if there is any adjustment that can be made to close the door totally shut without having to pull out the box.
Just another note....the centre lever doesn't sit in the up position (cool) when i let go of it as it springs down a little, but it will sit in the down (heat)
Deleted
Quote from: Royce Peterson on January 31, 2020, 10:18:55 PM
Disagree. The valve opens when vacuum is applied. Otherwise it is closed.
Quote from: Bob Gaines on January 29, 2020, 01:26:32 PM
Quote from: Royce Peterson on January 29, 2020, 11:11:45 AM
Bob the valve that ports vacuum to the hot water valve is closed unless the temp cable is moved to the lower position. So water only flows then. It does not matter if the fan switch is on or off. So the only time heat should come from the system is when the cable is moved down, which also opens the heat door. The hot water valves are spring loaded shut. When they fail, they fail shut. The heater core does get warm anyway just from the stagnant water eventually getting warm through contact. But it will not be as warm as it could be if the valve were open.
The fan switch controls the air conditioning compressor power, in combination with the icing switch. Turning the fan on will supply 12 volts to the fan clutch unless interrupted by an open icing switch.
If you are getting warm air in the cabin it is most likely the foam rubber in the heater / AC box is rotten and allowing air to get through / around the closed heat door.
Another possibility would be someone has purposely routed vacuum to the heater valve so it is open any time the engine is running. You can check this easily by removing the vacuum hose from the top of it. There should only be vacuum when the heat lever is at the bottom and the engine is running.
Quote from: Bob Gaines on January 28, 2020, 10:29:06 PM
Quote from: Rickmustang on January 28, 2020, 09:27:10 PM
Big blocks are hot, but did you bypass the heater core? If not the water valve in engine compartment may have failed. This assumes the vacuum controls are hooked up correctly under the dash. My 68 had AC, and my 70 big block car does too. I hate under dash projects due to all the AC stuff.
Probably not the heater hose valve. That valve only closes off the flow of water in the heater hose when the A/C is on. If the A/C is not on the water flows through the valve and through the heater core whether the heater is on or not . I suspect ether faulty vacuum or faulty duct function in the heater box.
Royce,I did not mention anything about a control in my post only the heater hose valve. If you think that the water valve on the heater hose is normally closed then you are misinformed . The valve closes when vacuum is applied . It snaps back open when that vacuum stops. It is designed so that if the A/C is on the flow of hot water is stopped so that the heater core is not fighting the evaporator core.
Royce ,you are wrong . You obviously do not have a working valve to double check otherwise you would not make that incorrect observation. I on the other have refurbished used and NOS ones on hand to verify the correct normally open observation. It is easy enough to test by blowing through the nipple in the direction of the arrow marked on the valve . When you apply vacuum to the diaphragm the valve shuts off the flow. Which I did test to confirm. I respectfully suggest you do the same .
Bob,
Apologies - you are so right! I was on the road and got home tonight. It works exactly the opposite of what I thought I remembered. You are correct sir!
Quote from: Royce Peterson on February 01, 2020, 06:24:39 PM
Bob,
Apologies - you are so right! I was on the road and got home tonight. It works exactly the opposite of what I thought I remembered. You are correct sir!
Thank you for the honorable apology . It is of course accepted.
You are welcome and appreciated Bob - just trying to help.
I drove a 1967 Cougar as my daily driver from 1977 until 1990 in the process adding 300,000 miles to the odometer. It was a factory AC car and Texas is hot much of the year, so I had to keep it operating. One of the things that had trouble several times was the water valve vacuum switch which is located on the front of the unit just below the glove box. These little valves sometimes stick open. Other times they stick closed. Or they fall apart causing a vacuum leak. In any case when they malfunction you can have no heat or no AC or a total loss of vacuum to the system.
The factory shop manual has a handy chart listing when each hose is supposed to have vacuum (v) or not have vacuum (nv). This is what I always went to when I had trouble getting either heat or AC from the system.
Royce, thank you for you sage advice.
That diagram was reproduced in the link I had attached earlier and is helpful.
My vacuum operated valve ( door/flap actuator ) seems to be moving and holding vacuum. However what I found was that when the door should be closed and the fan is switched on I feel the same amount of air flowing to the floor as when it is open so I'm wondering if there is something not allowing the door to stay closed. It is closed when i direct air to the screen and face level as no air goes to the floor.
As for the heat in the car... God yes they are hot inside! I have no AC and I sweat my posterior off when it's more than 60 out. I drive the car to services on Sunday sometimes and if I wear a suit I sweat in the 12 mile drive.
Sadly, the non-AC cars have hot water circulating through the core regardless of if the heater is on or off.
-Keith
Well in that case I should just gas up my a/c and run it when driving.
Being that yours is a non a/c car does it stay cooler for you if you ran the heater setting to cool on the temp setting (middle lever) and screen or face vents as opposed to floor?
Also if you select off and put the fan on do you get air coming out of the floor level?
Yes, I get movement via the bottom duct. I usually pull the vent knob on the left next to the hand brake. The door on the passenger side just feels hot so It stays closed. I am finishing the restoration of the factory unit I have and waiting for the return chrome compressor, idlers, power steering pulley, power steering and alternator pulley.
The AC set up requires the change to the 7AC GT350 power steering pulley single groove alternator and C5 crank pulley. I guess I'll set all the originals aside in case I need to return to stock.
-Keith
So I've had my KR for a few years now. This might be simplistic and I would think noticeable, but when I first got the car I noted a good amount heat coming up thru the 4 speed shifter area. The rubber boot that covers the mechanism under the floor was missing. Replaced that and had a noticeable decrease in cabin heat. 8)
Quote from: Sxty8KR on February 27, 2020, 06:04:07 PM
So I've had my KR for a few years now. This might be simplistic and I would think noticeable, but when I first got the car I noted a good amount heat coming up thru the 4 speed shifter area. The rubber boot that covers the mechanism under the floor was missing. Replaced that and had a noticeable decrease in cabin heat. 8)
Thanks for the information. My lower boot has been cut away by a previous owner so I'll be replacing that and see how it goes.
We removed the rugs / factory insulation on our cars. We then installed the aluminum insulation thermal sound deadner sheets on the floor and as high as we could get them in the interior fire wall.
Then reinstalled the factory insulation and the carpet. These aluminum sheets with the special backing diverted the heat from entering into our interior.
Quote from: FL SAAC TONY on February 27, 2020, 06:36:41 PM
We removed the rugs / factory insulation on our cars. We then installed the aluminum insulation thermal sound deadner sheets on the floor and as high as we could get them in the interior fire wall.
Then reinstalled the factory insulation and the carpet. These aluminum sheets with the special backing diverted the heat from entering into our interior.
Sounds like that would work...Did you use something like Dynamat?
Yes we did
Quote from: GT350AUS on February 27, 2020, 06:53:08 PM
Quote from: FL SAAC TONY on February 27, 2020, 06:36:41 PM
We removed the rugs / factory insulation on our cars. We then installed the aluminum insulation thermal sound deadner sheets on the floor and as high as we could get them in the interior fire wall.
Then reinstalled the factory insulation and the carpet. These aluminum sheets with the special backing diverted the heat from entering into our interior.
Sounds like that would work...Did you use something like Dynamat?
Tony
How far back did you go?
Did you remove the rear seat and fit it under it?
Ross
When we painted them, all the interior was taken out. So all the floor boards and again as high as we could get to towards the front wall. Make sure that you get all the surfaces as clean as possible so the rubber / sticky side sticks real well.
Quote from: GT350AUS on February 27, 2020, 07:08:32 PM
Tony
How far back did you go?
Did you remove the rear seat and fit it under it?
Ross
Quote from: Sxty8KR on February 27, 2020, 06:04:07 PM
So I've had my KR for a few years now. This might be simplistic and I would think noticeable, but when I first got the car I noted a good amount heat coming up thru the 4 speed shifter area. The rubber boot that covers the mechanism under the floor was missing. Replaced that and had a noticeable decrease in cabin heat. 8)
Does the lower boot sit over the shitft mechanism with linkages bolted to box or does it sit over it then screwed to the floor
With the shift handle then being attached through the lower boot that is screwed to the floor?
Mine has nothing there so I dont have a reference point
Replaced the lower and upper boot today and my heat problem is solved.
Thanks for everyone who chimed in on this.