Hey CO. With air temperature hovering around triple digits I've got a problem. My non-ac car blows hot air out of the floor and vents after the engine is warmed up. Now I checked the blend door and the cable is hooked up and has full travel and when I turn it to heat it gets really freakin hot in there. Is this normal without the coolant shutoff to the heater core that ac cars have? I want to drive my car but I don't want to be sweating like a ***** in church after 15 minutes in the car. My kick panel vents open and close but I do not have any of the soft vents that go between the plastic tubes under the dash. There was no evidence of any being there so I assume they were removed. Thanks in advance.

 

This is completely normal. The non-A/C vents are a cruel joke at temperatures over about 55°F.

They should be labelled "Convection Oven" rather than "Vent."

Even with a hot water shut-off, it won't be much better.

- Eric

 

Not much you can do about it except sweat it out or add A/C. A lot of the heat comes from your engine, which heats the heater box housing and the rest of the firewall.
I have one non-AC car ind it does the same. Above 90* and over 15 minutes cannot be done without sweat.

One thing to check is to make sure your hood-cowl seal is there and sealing to help prevent engine heat from being sucked right into the air intake. Of course most hoods for non-AC cars have engine vents right at the back to do just what you do not want - what were they thinking??

You can try cutting off the coolant flow to the heater core (clamp on the smaller back hose) and see if that is better. I doubt by much, but who knows!

 

Even after the "thanks in advance"??? You guys are killin' me. I have an oai hood so there are no vents back there and I did install the cowl seal after the 1'st unbearable day and it helped a little. Although I want a bone-stock restoration I'm not giving up here. If anyone has any ideas let me know. And if I make this thing tolerable to drive in the summer I'll update you. Now I know why all my a/c cars have cherry window mechanisms and rollers!

 

As has been said, it won't be great in the triple digits, no matter what you do without A/C. Try the shutoff valve for the heater. At least it'll keep the hot water out of the heater core. Those air doors frequently don't stop all the air flow through the core.

 

Well, going to try something! Any relarelation to oldzie ozzie?

 

If you stop at the 7-Eleven, you could fill your plenum with ice before every drive.

Probably last about half an hour.

- Eric

 

The non AC cars are what they are. I know, I have one. The way your 'Heater' controls are designed do not allow the heater core to be bypassed. What they will do is close the blend door so none of the heat from the heater core should go to the cabin. Not a perfect world though.

Now as for the side (upper and lower) vents are concerned? They are NOT fed from the heater core. They are fed from ambient air temperature that comes in from the cowl vents, and you do have those even with an OAI hood. That means that whatever the outside air temp is, that's what you're getting through those vents. As others have alluded, it can be more like a convection oven at times. Only solution really is to roll down the windows for better flow through. Even at that with triple digit temps, you're going to stick to the seat. Sorry.

 

OK. But this just occurred to me. All my a/c cars, when the a/c was just on vent or even if it plain ol' didn't work weren't anywhere near as hot inside as this thing! I know I'm getting older but I'm not getting exponentially sissier! So to put it another way my a/c cars didn't heat up the inside when they were just on "vent".

 

Mine all did. Maybe you were just lucky.

- Eric

 

You were posting as I was typing Allan. But I think that the open vents without being connected with the under dash "hose" are free to spew hot air into the cabin. The kick panel vents should at least try to cut off some hot air coming from the heater plenum if the blend door is open or not right?

 

I'm not all that lucky of a person MD. Unless you count bad luck. There has got to be a way. Maybe this will become my newest futile quest!

 

The lower and upper vents are not related to any part of the actual heating system, so the position of the heater control is really a non issue for them. They simply allow a channel for ambient outside air into the car. Shane (oldzzy) rebuild his non ac venting system. Here's a link to the section where you can see how the outside blend door is hinged and operated by the cables. Shane's 70 Restoration

EDIT: The only real way to keep the car cool in extreme heat is to install an AC system, as others have mentioned.

 

disconnect the hoses off the heater core.get a pipe that the hoses will slide over,clamp them ,and that will cut off some of your heat problem.

 

OK Allan you are right. And I only had this dash out a month ago! The missing hoses are from plenum to defroster vents. So now my plan of attack will be to cut flow to the heater core and remove the heater plenum and make the blend door seal better. As iI said, I want a bone-stock restoration. I just ddon't want to suffer for it.

 

I understand completely. Wishing you all the best in the heat. Do you still have those plenum hoses? If not you'll have to replace them with standard AC flex vent hose. The old rectangular ones aren't reproduced, and the old ones are likely very brittle and smelly too.

If do remove the coolant flow to the heater core, you will not have heat at any time when the temp gets cold. Maybe I misunderstood what you want to do though. Doesn't Albuquerque have one of those funny micro climate issues with heat and cold? The dash is a lot of fun isn't it? Got some practice on them out at the bone yard. I think I could take one out now in less than 2 hours. AC cars would take a little longer.

 

Ah! I wish I had the old ones. I think the previous owner robbed them for his other cars as mine had not been on the road in 28 years. And no remnants! Cold weather is not an issue as I don't intend on driving in the cold weather (common sense would say your going to burn anyway). I am after a fair weather car so to speak. If the ambient temp is what comes through the vents that's fine with me.

 

Have you considered removing the carpets and installing one of the aftermarket floor insulation kits? I believe a couple on here have done it and may post on it's effectiveness. Myself, I've found that you never open the kick panel vents in the Summertime, but I do open the dash vents and run with the windows down.

 

I'm sure the fat mat, dynamat, jute, or other sound deadener will also reduce heat from the floor boards. If doing the floor, might as well do the doors, quarters and roof too.

Just curious - if you wouldn't open the kick panel vents in the Summer, when do you open them? I've always used both upper and lowers for better air circulation at higher speeds. Only in AB, we typically don't get triple digit heat numbers. Cruising around town at low speed I just leave all the windows down and open all the vents too.

 

Well the worst of the heat is not coming from the floor or firewall. There is hot hot air coming out of the floor vent and therefore the unfinished defroster vent. Now that I have looked at the system better it makes no damn sense for the blend door to TRY to shut off airflow while still going through the heater core (with no hot water shutoff valve) all while the blower motor is going. The cowl vents are not outside air temp either but they are better. An a/c equipped car redirects the airflow from the heater core to the evaperator. And seals far better than a non a/c system.

 

Is the fitting that the heater hose connects to on the back of the intake manifold, a stock fitting, or has it been replaced?
The stock one has a 'restriction' in it to only allow a little flow to the heater core. Perhaps yours doesn't have a restriction in it, and is allowing full flow to the core.

Last year I took out all of the AC equipment from my car, and installed an AC delete plate. Since I'm rebuilding the engine, I have found that the stock heater control valve is corroded up, and want to replace it with a 'restricted' non AC fitting, and am curious if I'll have excess heat in the car also.

 

I'm confident its the original, Midrange. As stated in a previous post this car up until 2 weeks ago had not been on the road since 1985. I spent much time blasting housepaint off of the intake in the cabinet and don't remember the fitting looking restricted. I don't think it will matter either. The ambient air here feels much better than heater core air. But there are cruise nights this week and I will first use a pair of hose pinch pliers to back-to-back see if I am happier or just less miserable! I will update because I already know others in the olds community are suffering and I am going to make this car more comfortable to drive. It cost me a girlfriend to build and I don't think I can keep a new one if I don't fix this.

 

OK. So I made some progress here guys. I found a pretty cool manual (cable operated) shutoff valve from Napa. Got it stealthily installed in the hose to the water pump. Now I'm going to make a bracket to allow the cable to be operated by the warm/cold lever on the control head (haven't figured that out yet). But the kick panel vents still breathe hellfire and I have to close them. I still have the original seal at the back of the hood (it looks pretty good) but it may not seal all that well. And in the meantime the car has been far more tolerable to drive with the hose pinched off and the kick vents shut.

 

Have you confirmed that the blend door is indeed closing off fully?

 

On a cool summer night I might open the kick panel vents. I rarely had the need or the urge to run with them open. Also, I never used the heat setting in summer (as suggested in very first post,"when I turn it to heat, it gets really freaking hot in there,") unless I was in bumper to bumper, stop and go traffic, as in Woodward Dream Cruise and I needed to cool engine down a bit. Hope this helps.

 

You know, if you can't get it cooled down, gut your interior and clad it with dynamat or fatmat or such materials for better insulation from your engine heat.
I think it works pretty well and would help you a lot at least at the toe boards and up the firewall (if you can get it up in there.)
Does your dash need to be pulled and restored? Lots of MAWs can happen here!
<<ducking for the internet bomb shelter>>

 

Yes, the blend door is closing fully. The reason I mentioned that in the first post was to illustrate that the blend door is funtioning. I did just have the dash out also but I'm not having problem with the floor being hot, just the air coming through the vents.

 

It's almost triple diget you have no AC. It's going to be stinking hot in the car PERIOD! Shut off the blower and live with it or get an AC car.
I'm sorry to be rude but that's the way it is.

 

I hate to agree, but, yeah.

You're sitting in a greenhouse, under glass, in the sun, with a 210°, 600 pound engine blasting heat out its radiator in front of you, and 300° exhaust pipes and mufflers underneath you, cooking you like a steak.

Only way to cool that down is with A/C.

- Eric