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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Heater Core!!!

  • Thread starter Thread starter djk8705
  • Start date Start date Jan 5, 2004

djk8705

New Member
Sep 30, 2003
154
0
0
Fairfax, Va
Jan 5, 2004
#1
  • Jan 5, 2004
  • #1
Everyone has always said what a Pain in the A$$ it is to change one out but I think mine is time for a replacement, but u tell me. My heat wont work untill about 15-20 mins in the car and When is does it isnt hot its just like warm. I dont have A/C right now because its totally unhooked and broken, how come for the heater core is talks about A/C and antifreeze?..... Will not haveing the AC mean no heat??? .... this will be a first project for me with the heating system so If any of you could help me out.

THANKS
 

RyanSG

Founding Member
Oct 24, 2002
286
0
17
Allentown, Pa
Jan 5, 2004
#2
  • Jan 5, 2004
  • #2
o god the hearcore blows, basicly take apart your whole dash (unbolt it) slide it forward and then replace, but you'll need the a/c disconnected anyway, so thats a god thing. so do the heater core b4 you get the a/c fixed def
 

quiksilver9531

Founding Member
Oct 9, 2001
469
0
0
New Jersey
Jan 5, 2004
#3
  • Jan 5, 2004
  • #3
well im not an expert...but is there coolent underneath the passenger dash? it could be something as simple as the thermostat...maybe change that first and see if that fixes the heat.
 

HO93LX302

Founding Member
Jul 7, 2002
715
0
0
Naugatuck,CT
Jan 5, 2004
#4
  • Jan 5, 2004
  • #4
The ac has nothing to do with the heater, only defroster.. As for not getting heat for a while until the car is warmed up check your coolant level in the radiator.. Its probably low. start with that.. If the heater core was bad it would either leak or it would fog up the inside of the windsheild... And yes there a PITA to replace since you need to yank the dash out to do it.. Mines leaking and fogging so once spring comes it's just getting by passed
 

tvmango

New Member
Oct 27, 2003
667
0
0
bradenton florida
Jan 5, 2004
#5
  • Jan 5, 2004
  • #5
sounds like you have a possible thermostat problem, most mustang heater cores leak, not get clogged...i would try the $10.00, 10 minute thermostat first.....Whats the temp gauge showing in all of this?
 

djk8705

New Member
Sep 30, 2003
154
0
0
Fairfax, Va
Jan 5, 2004
#6
  • Jan 5, 2004
  • #6
The temp guage is usually very low and after awhile when it comes up thats when the heat starts to work.

Where would the thermostat for the heater go???
 

djk8705

New Member
Sep 30, 2003
154
0
0
Fairfax, Va
Jan 5, 2004
#7
  • Jan 5, 2004
  • #7
Also I just checked my radiator fluid, and yes I am halfway between the "cold fill line" and the end of the bottel. Would that much make all that differnce???

THanks in advanced
 
1

1BAD89GT

New Member
Jan 2, 2004
87
0
0
Oklahoma
Jan 6, 2004
#8
  • Jan 6, 2004
  • #8
djk8705 said:
The temp guage is usually very low and after awhile when it comes up thats when the heat starts to work.

Where would the thermostat for the heater go???
Click to expand...

The thermostat is located at the front of the lower intake where the upper rad hose connects to the lower intake.if replacing the thermostat doesnt work try removing the coolant and return line from heater core at the firewall and use and air gun and compressor and blow high pressure air through heater core,ive had to do that before its amazing to see some of the crap that comes out of there.
 

djk8705

New Member
Sep 30, 2003
154
0
0
Fairfax, Va
Jan 6, 2004
#9
  • Jan 6, 2004
  • #9
1BAD89GT said:
try removing the coolant and return line from heater core at the firewall .
Click to expand...


Would you be talking about removing the radiator coolent or does the heater core have its own seperate system??

Also do u know if there is any breather valve to get the air out of ur radiator lines and what not when adding more to it? or will i have to just run the engine and let it suck it thru???


THanks
 

tvmango

New Member
Oct 27, 2003
667
0
0
bradenton florida
Jan 6, 2004
#10
  • Jan 6, 2004
  • #10
dude change your thermostat,, if you temp is staying low, and then goes up when the heat works, it because the t-stat is sticking open,, the theromstat takes 10 minutes to change, but 20 minutes to clean up the coolant (jk),, it is messy, but drain out some coolant first.. there is a little petcock on the pass side back of the rediator to let coolant out..it is in behind where the upper radiator hose is bolted to the lower intake.. i hope this helps..
 
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