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Topic: No heat question (Read 7372 times) previous topic - next topic

No heat question

So my freshly built 83 TC is on the road and turned out great. Getting the last few bugs worked out now and my biggest one is I have no heat.

 My motor has plenty of hot coolant flowing through the heater hoses. My MicroSquirt shows 190* engine temps. The heater core was said to be brand new before I got the car. All of my HVAC controls seem to work as they should but I need to pull the glovebox back out and try to see if the door in the box for the fresh air at the cowl is stuck open.

Anybody know what or where to look for the fresh air door ?
Brian R.
88 2.3t Ranger
83 TC  gt40p motor,Vortech,TFS1 cam,long tubes,MS PnP,T5,8.8,17x9 Cobra 17s

No heat question

Reply #1
ATC or Manual?
Is the air coming out somewhere, floor or defrost?

No heat question

Reply #2
Manual

All HVAC functions work like they should, just no heat in the air being blown out.
Brian R.
88 2.3t Ranger
83 TC  gt40p motor,Vortech,TFS1 cam,long tubes,MS PnP,T5,8.8,17x9 Cobra 17s

No heat question

Reply #3
Did you purge the cooling system properly?  An air-locked cooling system usually stalls coolant flow through the heater core.  Try loosening the clamp at the firewall and using a bent pick to let air out between the hose and the nipple.

No heat question

Reply #4
With both hoses hot, you're gonna have to figure out why the air isn't routing through the core...

I think somewhere around here are links to various year EVTMs that should picture the door operation inside the plenum..

No heat question

Reply #5
Following this thread because I'm having the same issue in my '86 XR-7.    New thermostat, radiator, hoses and heater core but still not heat :(
1986 Mercury Cougar XR-7 Turbo-charged 5-speed.
Owned 22 years.

No heat question

Reply #6
The temperature control operates the temperature blend door mechanically with a cable.
If the blend door stays in the cold position, the air will bypass the heater core.
I see in a shop manual picture that the door is spring loaded. I can't tell which way it will go if the cable is disconnected or broke.

After studying the pics, I have convinced myself the door is spring loaded to go to the cold side.

No heat question

Reply #7
Pics:

No heat question

Reply #8
HA! You nailed it.  That self adjusting clip in view A I found under the floor mat and didnt know what it was for! Now to go find where I put it and reinstall it. Thank you!
Brian R.
88 2.3t Ranger
83 TC  gt40p motor,Vortech,TFS1 cam,long tubes,MS PnP,T5,8.8,17x9 Cobra 17s

No heat question

Reply #9
You're welcome.

No heat question

Reply #10
"... loosening the clamp at the firewall and using a bent pick to let air out ..."

May I ask for a little clarification on how to actually do this, please ??
.. never tried something like that.

Thanks !

No heat question

Reply #11
Quote from: AlabamaWildman;458286
"... loosening the clamp at the firewall and using a bent pick to let air out ..."

May I ask for a little clarification on how to actually do this, please ??
.. never tried something like that.

Thanks !
If coolant is not circulating through core, either it's blocked, there is a collapsed hose or water pump isn't operating(seen ones with rotted impellers move coolant through radiator but not have enough flow to push coolant through heater hoses)... With properly operating components, burping a heater core should not be necessary...

No heat question

Reply #12
Okay, next question:  New Parts:  Radiator, water pump, thermostat, upper and lower radiator hoses - STILL NO heat.  When moving the temperature selector from cold to hot, I am not hearing any sort of 'flap' moving under the dash.  Is there an easy way to move this thing manually without taking the whole dash apart?  I realize that moving it manually will mean that my heat stays on but, at this point, I'm good with that for a few months :)
1986 Mercury Cougar XR-7 Turbo-charged 5-speed.
Owned 22 years.

No heat question

Reply #13
Quote from: CougarGal;458294
Okay, next question:  New Parts:  Radiator, water pump, thermostat, upper and lower radiator hoses - STILL NO heat.  When moving the temperature selector from cold to hot, I am not hearing any sort of 'flap' moving under the dash.  Is there an easy way to move this thing manually without taking the whole dash apart?  I realize that moving it manually will mean that my heat stays on but, at this point, I'm good with that for a few months :)

Heater hoses get warm?
Manual or Automatic Temperature Control (ATC) ?

No heat question

Reply #14
Quote from: softtouch;458301
Heater hoses get warm?
Manual or ATC?

Both heater hoses get HOT and it's the manual slide type switch.
1986 Mercury Cougar XR-7 Turbo-charged 5-speed.
Owned 22 years.