This windows on my 1985 F150 5.0 A/C started to fog when the HVAC was turned to hot.

The old core was beginning to leak but the issue I have is the replacement will fit heater core from Autozone looks similar but doesn’t fit. Has anyone else run into this? What was the resolution?

 

What does "not fit" mean? How does it not fit?


Why was the numbers marked on the box the way it is? Was the box opened before you got it?
Only other one I see listed is this one.
https://www.autozone.com/cooling-hea..._406242_0_5281
You cant always go by pictures but this one may work.
Oh I had 84 saved so that is why it said 1984 truck but I cant see a year making that much of a difference.
Dave ----

 

The cores appear to be very similar except for the top tank,
the OE is offset and the replacement isn’t and that portion of the tank is keeping the core from going into place.

 

I exchanged the core for another with the same part number; this core tank had rounded corners and fit into place.

 

Good to hear you got it worked out.
I think with the part numbers marked the way they were there was an issue with it before and someone just put it back into the system.
Dave ----

 

1980/86 F100/350 & Bronco: THREE different heater cores:

1) Standard heater.

2) High output heater.

3) Factory installed integral A/C & Hi/Low Comfort Vent System

 

How can I check whether I have the "3) Factory installed integral A/C & Hi/Low Comfort Vent System"?

I would like to have a "furnace mode" in preparation for NE winters. Can a high-output heater be installed to replace the standard heater in an integral a/c system?

 

Also, does anyone know about the auxiliary heaters that were available for 80-86 Broncos?

From the Master Parts Catalog 80/89, section Heat & A/C, page 16864:


Is this installed in the engine bay?

In a related question, my truck (86 EB Bronco) did not have the back window defroster switch, or the heated glass, and I want to install it. When looking for the control assy (which I think means the defroster switch) I found this:



specifically
81/83 U150 -- aux heater
81/84 U150 -- w/o aux heater

Help Wanted!

 

I believe someone did look one of those questions up before; No, the high output heater is not an option with factory A/C is what they came up with.

I have found if you take the system apart and get all the pencils, pins, watches, candy, and other junk out of the defroster area and down where the air comes through the cab, and then take out the A/C coil and clean all the mud out of it, the regular heater will run you out of the cab. It works very well if everything is in good shape.

 

Noted, and thanks. I plan on overhauling the heat-a/c as you described, which hopefully will resolve the problem, or at least help troubleshoot it. At the moment, I can breathe into my cupped hands and generate more warm air than the heater on high.

 

Yeah, the standard heaters on these things rock, but I agree with Dave and think you'd be well off to clean everything out and try that before fixing what probably isn't broken.

I have never seen this "hi/low comfort-vent system" thing, I wonder if it in fact ever existed even though it's in the parts book, or maybe it's just a fancy-sounding Marketing name for Air Conditioning. Ford was like that especially with paint colors; what was called Champagne Gold on a Lincoln Mark V was called School Bus Yellow on a Pinto.

Concerning that aux heater thing in the drawing (never seen one in real life, it's quite possibly a myth that never made it to production) I imagine it was like they do in a school bus - coolant tubes with rubber hoses on the ends running the length of the vehicle from the engine to the rear, a small radiator (heater core) + fan in the passenger compartment providing additional heat "back there."

 

In my experience, the AC evaporator (aka coil) is the main place where clogging occurs. On trucks with factory air (easily identified by the four vents on the face of the dash), all HVAC airflow passes through the evaporator, regardless of the mode selected. The evaporator is the first restriction after the fan, so this is where outside crap such as leaves and pine needles will collect.

Access to the evaporator isn't too bad. Under the hood, remove the plenum cover closest to the engine. You can see the two evaporator lines coming out from the case split line just aft of the receiver/dryer. Most of the screws are in plain sight under the hood. One screw near the bottom passes through the firewall. Access is from the passenger footwell near the transmission hump. You may have to peel the carpet back slightly.

Once the cover is off under the hood, you can swing the evaporator (and attached receiver/dryer) inboard a few inches for cleaning. The flex lines allow for movement without having to discharge the refrigerant.

Expect to find the outboard face of the evaporator totally covered in crud. Use a shop vac on the upstream (outboard) side and compressed air from the downstream side. The evaporator is like a small radiator, with lots of small air passages between the tubes and fins. Use a small inspection mirror and flashlight to make sure the passages are clear. Moisture collects there when the AC is running, so normal dust accumulation turns into a poor man's cement. It may help to spray the evaporator with water to soften the cement for removal. ​​​To help make future accumulation easier to clean, I fitted a piece of coarse screen on the upstream side.

While you're in there, remove the blower motor and resistor pack to clean the ducts, too. This is very important because crud collecting at the resistor pack is a known fire hazard. Details, pictures, and several cheap jokes here:

https://www.ford-trucks.com/forums/1...n-the-cab.html

I'm with Dave on his assessment of the heater's capability once everything is cleaned out. My wife, who suffers from Digitalis Popsicallis, absolutely loves the flamethrower-like heat in our truck.

 

kr98664, I appreciate the step-by-step guide. In a few weeks I'll start this task and will reference this post. I had in mind a mesh grille for the cowl and I will use this time to see if I can make a cab air filter.

 

Thanks, ctubutis. I can't imagine it would go in the back, there's room but surely Ford wouldn't dump a box in the corner or the middle of the cargo area... but it doesn't seem reasonable to place it in the engine compartment either as it does not look air tight like the duct work behind the dash.

 

Hi Bill, using the Master Parts Catalog, I can’t find the box and lid for the auxiliary heater (see pic in my earlier post). That is, I can’t find 18447 or 18A447.

Would you you know if these parts exist elsewhere (eg microfiche) or they were relabeled (Ford’s frustrating habit of changing product codes)?

I am starting to think it’s as ctubutis describes, “a myth that never made it to production.”