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heater core replacement

  • Thread starter Thread starter mustang88GT
  • Start date Start date Jul 5, 2004

mustang88GT

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Jun 1, 2003
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Charlotte, North Carolina
Jul 5, 2004
#1
  • Jul 5, 2004
  • #1
heater core went bad a few months ago and i figure i had better fix it before winter and i am frezzing.... i know that it is a whole weekend project where every dash piece has to come off inorder to get to the heater core, but i was wondering if it is posible to replace the heater core with out discharging all the R-12. the reason i dont want to discharge all of the regregerent is because i dont wanna convert to 134a and my car has really cold ac although i rarely use it.... thanks
 

89stangalang

New Member
Dec 23, 2003
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Jul 5, 2004
#2
  • Jul 5, 2004
  • #2
I think you have to discharge it so you can lower the inner heater core housing in the car. The only way you will be able to properly lower it to get to the heater core is to disconnect those lines. I am not completely sure but I have had to change this part 3 times in my car. I actually just changed it last Friday. It only took about 8 hours for me though as i am now a pro at doing it.....lol. Good luck man.
 

black82fiveoh

Founding Member
Jan 4, 2002
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madison wisconsin
Jul 5, 2004
#3
  • Jul 5, 2004
  • #3
Im pretty sure you do have to discharge...

on a side note:I did mine on my capri(no a/c)took me about 10-15 min. how come it took you so long?? j/k

you could have a shop evac it, but I dont know if they'd keep it for you while you replaced the heater core. try to find a shop who will do it for you(evac and recharge)

GOODLUCK

edit**I know someone who did it without discharge. just had to bend the pipes a little...just take your time and be careful
 

jrichker

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Jul 5, 2004
#4
  • Jul 5, 2004
  • #4
See http://home.netcom.com/~skent/mustang/1990/heater_core/hcore.html for help. Done carefully, you don't have to remove the A/C evaporator or bleed off the Freon.
 

mustang88GT

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Charlotte, North Carolina
Jul 5, 2004
#5
  • Jul 5, 2004
  • #5
jrichker said:
See http://home.netcom.com/~skent/mustang/1990/heater_core/hcore.html for help. Done carefully, you don't have to remove the A/C evaporator or bleed off the Freon.
Click to expand...

u are the man every question i ahve had u have always helped thanks man
 

ECU5.0

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Jan 10, 2004
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raleigh, nc
Jul 5, 2004
#6
  • Jul 5, 2004
  • #6
i dont see how you would be able to pull the hvac box out enough without unhooking the ac lines. i did mine last thanksgiving and could barely get the box out enough with the lines unhooked. it took me like 7 hours to do the entire job
 

88stangmangt

Active Member
Nov 25, 2003
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Stafford,VA
Jul 5, 2004
#7
  • Jul 5, 2004
  • #7
be carefull to mark everything cause little elec gremlins love to come out and play.
 

ECU5.0

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Jul 5, 2004
#8
  • Jul 5, 2004
  • #8
"install is opposite of removal"-Haynes manual
 

88stangmangt

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Nov 25, 2003
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Stafford,VA
Jul 5, 2004
#9
  • Jul 5, 2004
  • #9
ECU5.0 said:
"install is opposite of removal"-Haynes manual
Click to expand...
it isnt always that easy............
 

ECU5.0

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raleigh, nc
Jul 5, 2004
#10
  • Jul 5, 2004
  • #10
88stangmangt said:
it isnt always that easy............
Click to expand...

yeah i know, it was joke because thats all that haynes manuals say
 

88stangmangt

Active Member
Nov 25, 2003
2,332
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Stafford,VA
Jul 7, 2004
#11
  • Jul 7, 2004
  • #11
ECU5.0 said:
yeah i know, it was joke because thats all that haynes manuals say
Click to expand...
ooh hahaha isnt that true. most of the time they tear em down when they are brand new so they dont have to worry about breaking 15 year old $hit or any of those problems.
 

webestang

New Member
Jul 5, 2004
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St. Louis, MO.
Jul 7, 2004
#12
  • Jul 7, 2004
  • #12
I just replaced my heater core without discharging the AC.
Go to mustanggt.org click links then tech. It took 8 hours but only cost me $42 for the core. I removed the console, dash, gauges (disconnet speedo cable first from trans) take off the brakect for the AC evaporator to get to the nuts that hold the heater box against the firewall. You can take the front two screws off for the cover and pry the cover up to gain access to the core.
Take your time and it is not as hard as you think.
Good Luck,
Scott
 

mr5o

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Jan 28, 2001
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Ontario, Canada
Jul 7, 2004
#13
  • Jul 7, 2004
  • #13
ive done it in 2 cars the first took 2 of us 4.5 hours the 2nd only took me 4 by my self ...not workin to hard ....just pay attention to where stuff goes and it'll be easy
 

bmorrisj

Member
Sep 26, 2003
449
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17
Buena Park, CA
Jul 7, 2004
#14
  • Jul 7, 2004
  • #14
no heater core for me please....
 

mustang88GT

New Member
Jun 1, 2003
186
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0
Charlotte, North Carolina
Jul 16, 2004
#15
  • Jul 16, 2004
  • #15
after 8 hours of workin on my car the heater core is in.... also fixed my ac ( shorted wires and relay which was easily found with a test light and a scymatic) have not tested to see if the heater core works yet but i am almost positive it will work i am going to make one of those restrictors tommorrow... ended up with about 4 screws left opps.. oh well everything is sturdy... thanks for the help
 
B

blk92stangg

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Jan 30, 2004
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Hawaii
Jul 17, 2004
#16
  • Jul 17, 2004
  • #16
Did you clean all the old black crap out of the lip where the heater box mated? I have heard that that black stuff keeps the core from seating correctly and is a cause for leaks down the road. I wish I could find the link for that article I was reading. I have no real need for heat here in Hawaii, so I took the easy way out and bypassed the heater.
 

UMDSmith

Member
Feb 10, 2004
226
0
17
Salisbury, Maryland
Jul 17, 2004
#17
  • Jul 17, 2004
  • #17
My first time took me about 8 hours solo. I chucked all the a/c stuff since it never worked anyways, but my advice for you, you can remove ALL the screws from the trim with a power screwdriver, but when you put the screws back in, ALWAYS ALWAYS hand tighten. The 15 year old plastic can't take power screwdrivers, even on lower settings. This will save you a lot of cursing and broken parts.
 

mustang88GT

New Member
Jun 1, 2003
186
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0
Charlotte, North Carolina
Jul 18, 2004
#18
  • Jul 18, 2004
  • #18
i made a restrictor out of a copper cap that i drilled a 5/16ths hole in and clamped it in the inlet hose. Heats up quick and pretty hot. i got as much of teh black sealent off that i could.
 
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