It's still awfully cold

[Libby]

I posted a question a couple of weeks ago about my 67's cold air problem (lots of air, but no heat). I've since had the heater core worked on--apparently, it was stuffed full of crud. I also had a new plenum installed; I guess the original cardboard just wasn't meant to last 38 years . Anyway, I've got great air, but still little heat. The thermostat is a 160*, but if I use a 180* she'll overheat. Since I had this work done, I've noticed the temp. gauge isn't moving over quite as much as it used to, either. While browsing thru a Paddock catalog, I came across something called a "temperature sending unit". Now, I'm not real sure just what that is or what it does, but I'm wondering if it could be the problem. (is it painfully obvious that I don't know a heck of lot about cars?) Anybody have any ideas? I'm slowly driving my mechanic insane with this problem. Thanks for the help. Libby

[rwhite65]

If your car overheats with a 180, especially this time of year, there are other problems you should be looking at.
Ryan

[Gearhead999]

Car shouldn't overheat with 180, or 195. You have more problems then little heat.

With a 160 thermostat the heat temp will be on the COOL side. The temp. sender is only the sending unit for the gauge. Has nothing to do with the actual temperture of the engine and the amount of HEAT you receive from the car.

I'd find out why it overheat with 180 thermostat.

First thing I'd check.....If the heater core was "full of crud" then the radiator might be too. If it is this will cause the car to overheat.

Hope this gets you in the right direction.

[Libby]

Thanks for the info re: what the temp. sending unit actually does. The car doesn't overheat this time of year. I guess I shouldn't say she overheats in the summer; she does run hot, and sometime blows a little out of the overflow hose. As I've stated in a previous post, tho, she will overheat in the summer if a 180 thermostat is installed. (I've had this car, and driven her almost daily, since 1977, so I'm used to her little quirks) I'm also used to not having a lot of heat in the winter, but this is just not right.
My mechanic wants to remove & boil out the radiator (and the heater core again) once the weather gets a little warmer. When he replaced the plenum last week 2 of the original cables from the heater/defroster switch just fell apart, and he's got them temporarily rigged to work. He tells me that I also need the part that sits behind the switch plate that the cables connect to. (I'm probably describing this really badly, but hopefully someone will be able to decipher my meaning) Can anyone tell me what that part is called so I can order the right thing?
Sorry if this sounds as if it was written by a total doofus. I may not know much about cars, but I know what I like! Libby

[Kisner]

One other thing you might want to check is to make sure when you're adjusting the heater that the cables are actually moving the flaps to the correct positions to allow the warm air in. When I restored my 68, I took everything apart (heater box and all the other parts), cleaned them real good, re-painted them, installed all new gaskets, and threw the old heater core away. A new heater core only cost me I believe around $25 or $30. I also make sure that the various flaps and vents were opening and closing properly when I put it back together. I also replaced the switch on the front of the heater box (can't remember exactly what it's called) that the blower motor plugs into. If your hoses are routed properly to the heater core, there's no blockage anywhere, the heater box and plenum vents are opening correctly, and your thermostat is working properly, you should be getting warm air. My 2 cents.

[rwhite65]

I agree that u need to probably have your radiator cleaned, I think you will find that it is all plugged up too.
Ryan

[Libby]

Thanks, everyone, for the input. I believe the vents & flaps are all operating properly; the cable for the defrost lever is kind of rigged in place at the moment, pending replacement, but the other flaps appear to be doing just what they're supposed to do. Guess I'll just have to get the heater control & cables replaced, get the rad. & heater core boiled out, and see what happens. Libby

[Elvis]

Frustrating isn't it? I'm not as knowledgible about these things as some of the others but it is not really rocket science either. I've had some of the same issues with my '67. Firstly, I also had a problem with the coolant being burped out of the overflow. This would happen when the thermostat opened. I did all the things you are being told - cleaned out the radiator, replaced the heater core, etc but it still did the same thing. I had a 195 thermostat but I think it was opening too late causing the coolant to boil out when the thermostat finally opened. I replaced it with a 160 thermostat and it works great. Runs a bit cooler but thats OK with me.
Regarding the heat issue, here's my understanding of it, and once again, I'm a rank amateur. If the water control valve opens as it should the hot water should flow to the heater core allowing it to radiate a lot of heat. If the correct plenum doors open, the fan should blow air over the heater core and then out the heat/defrost vents. In my view, if that is not happening, either the heater core is not getting hot or the correct doors are not opening. Sorry if this is very simplistic but that is a sign of my simple mind. E.

[KiltedBanshees93GT]

"The King " brought up a good point. If when the cars running, the heater inlet hose is hot, odds are the hot water is getting to the core, and then getting stopped. If the core is new, then more than likely its not the problem.Thus doors/flaps should be further investigated.

Just my .02,
J

[Libby]

Thanks, guys. I realize I sound as if I don't have a clue but in truth, I don't! Unfortunately, my mechanic isn't a "Ford Man", so it's kind of hit-or-miss when it comes to figuring out just where the problem lies. Also unfortunately, it's hard to find a mechanic that doesn't need a computer to tell him to change the oil. Whenever I have a problem with my car, I tell to think of the most obscure, ridiculous thing that could go wrong & that will be the answer. Apparently, he just hasn't thought of it yet!
And Elvis, thanks for the info about your 160 therm. I got the distinct feeling other people thought I didn't know what I was talking about. Guess I'll get my new heater switch & cables, double check those plenum doors, flush the rad. & heater core, & hope for the best! Libby

[mustangII460]

I would say if your heater core was that bad so is your radiator. Get a new one. Also make sure you have a fan shroud and a good fan. (Not a electric one.) And no wimpy little flex fan.

How old is your water pump? Damaged/worn impellers can add to the problem. Wrong rotation pump etc.

Engine timing,

Coolant mix, type of coolant.

Air in system, drill 2 holes in thermostat to help bleed air. Stat in right.

Hoses colapsing,

Loose nut behind the wheel,

Get a later model overflow tank like in about a 85-86 LTD. Has washer and coolant. Blowing out a little is normal. But blowing out on the ground is embarassing.