Engine Replacing A Heater Core

Discussion in 'Fox 5.0 Mustang Tech' started by Don Fiveolio, Jul 1, 2006.


  1. strokedmustan66

    strokedmustan66 New Member

    Joined:
    Jul 24, 2010
    Messages:
    3
    Likes Received:
    0
    Trophy Points:
    0
    Thank you mustanguy, but I know there are 4 screws for the cover. I just need to know how people where able to get there box out past the back screws with out taking off the AC in my 89 gt.
    #61
  2. donald1956

    donald1956 New Member

    Joined:
    Nov 6, 2011
    Messages:
    5
    Likes Received:
    0
    Trophy Points:
    1
    why cant a hole be cut in firewall to replace heater core in 1989 mustang just replace it with new piece of metal curious has anyone ever tried this will it work it would make a hard job simple the next time
    #62
  3. FourEyed

    FourEyed Member

    Joined:
    Jan 10, 2011
    Messages:
    39
    Likes Received:
    0
    Trophy Points:
    7
    You maybe onto something..

    I think it would be great to be able get to it through the Cowl Vent Grill somehow.:shrug: you know.. just reach in there and pull the sucker out.:D
    #63
  4. 1killercoupe

    1killercoupe New Member

    Joined:
    Jan 28, 2012
    Messages:
    26
    Likes Received:
    0
    Trophy Points:
    1
    one of the best threads ever im doing mine 2morow with a lot more of a understanding than a repair manual gives keep up the good work
    #64
  5. twocent06

    twocent06 New Member

    Joined:
    Dec 21, 2012
    Messages:
    8
    Likes Received:
    0
    Trophy Points:
    1
    this is very helpful with the pix and all
    #65
  6. HDTony

    HDTony Member

    Joined:
    Oct 15, 2010
    Messages:
    134
    Likes Received:
    2
    Trophy Points:
    19
    glad this thread is here. just ordered mine up, soooooo not looking forward to doing this in my 91. my 65 took me about 45 minutes. this looks to be a day of hell
    #66
  7. The Shape

    The Shape Founding Member

    Joined:
    Jan 11, 2002
    Messages:
    2,249
    Likes Received:
    1
    Trophy Points:
    49
    Great thread, I did one about 8 years ago using just a haynes manual and it took me almost 8 hours. Wish I would have had all these tips and pictures handy then.
    #67
  8. 88gt373

    88gt373 Member

    Joined:
    Dec 29, 2010
    Messages:
    140
    Likes Received:
    2
    Trophy Points:
    18
    man... i had so many extra parts after i did mine.. ford didnt really need all those nuts and bolts. gave me a better 60-foot time
    #68
  9. 1200gt

    1200gt Member

    Joined:
    Nov 30, 1999
    Messages:
    305
    Likes Received:
    21
    Trophy Points:
    19
    That's the BEAUTY of Stangnet Forums, people still benefit from information no matter how old it is, as long as the car remain the same...:SN:

    BTW, I had my other 86 a/c done by an Certified A/C Mech. and I watched them pull the whole dash in one piece, never disconnecting MOST of the wiring (1986 convt.) and using coat-hangers to hold the dash up on the top-latches while they pulled out the heater box assembly. This was one of those days that I was glad that I snooped around looking into the shop while the guys worked.:pop:

    Now I have my other 86 vert to do myself - that-is, whenever I finally get some spare time! Working like a dog lately.

    This was a great post and for good reason it is a "STICKY" Post.
    #69
  10. 1200gt

    1200gt Member

    Joined:
    Nov 30, 1999
    Messages:
    305
    Likes Received:
    21
    Trophy Points:
    19
    Thisis a GOOD question!

    I was thinking the same thing. Would have been nice to have a panel to remove in the engine compartment where you could just slide it out from there; but then Ford would have missed out on all that Service Dept. Money:uzi: KILL-Hem! KILL-Hem!

    Actually as engineered, the engine would be in the way, but dreams never die!
    #70
  11. 1200gt

    1200gt Member

    Joined:
    Nov 30, 1999
    Messages:
    305
    Likes Received:
    21
    Trophy Points:
    19
    I wonder if all the YEAR FOX MUSTANG Heater Core Assembly's are the same???? ie. 79-93 Fox.
    #71
  12. RacEoHolic330

    RacEoHolic330 I like to dress like a pretty girl SN Certified Technician

    Joined:
    Mar 5, 2003
    Messages:
    3,504
    Likes Received:
    591
    Trophy Points:
    153
    They are all the same from 79-93.
    #72
  13. 7991LXnSHO

    7991LXnSHO Active Member

    Joined:
    Sep 1, 2010
    Messages:
    1,038
    Likes Received:
    84
    Trophy Points:
    49
    Actually, the early ones without factory air were at least installed differently. I thought that was a question asked when I got the part - "AC or no AC/dealer air?" My 1979 with dealer air was a lot simpler operation. Remover 4 (or so) screws for the glove box, and there was a nice plate on the firewall, that once removed let the heater core fall into your lap. I was SHOCKED first time I read what it might take on my 91! This is some of the worst engineering I have seen.
    #73
  14. RacEoHolic330

    RacEoHolic330 I like to dress like a pretty girl SN Certified Technician

    Joined:
    Mar 5, 2003
    Messages:
    3,504
    Likes Received:
    591
    Trophy Points:
    153
    Yes. I should have clarified that they are all the same during the years and ford didn't change the core designs, the a/c and non-a/c cores are definitely different though.
    #74
  15. HDTony

    HDTony Member

    Joined:
    Oct 15, 2010
    Messages:
    134
    Likes Received:
    2
    Trophy Points:
    19
    somebody shoot me!!

    Posting from under my dash
    #75
  16. mikestang63

    mikestang63 Mustang Master

    Joined:
    Aug 28, 2012
    Messages:
    3,441
    Likes Received:
    895
    Trophy Points:
    144
    You'd think by now somebody would have come out with a replacement firewall piece that you could either weld or screw in. It would make this PITA job like an hour instead of 6 hours. I've see guys hack and cut out the HVAC box and then silicone or putty it back together.
    #76
  17. HDTony

    HDTony Member

    Joined:
    Oct 15, 2010
    Messages:
    134
    Likes Received:
    2
    Trophy Points:
    19
    I have 3 screws out of this damn lid at this point. can not get to the passenger front screw. I think I may be cutting the cowl tomorrow and building a sheet metal piece. Ive got 4 evenings into this this already
    #77
  18. arnie93lx

    arnie93lx Member

    Joined:
    Oct 1, 2005
    Messages:
    38
    Likes Received:
    0
    Trophy Points:
    7
    Did you remove the heater box completely?
    #78
  19. Spaz

    Spaz Member

    Joined:
    Jan 5, 2013
    Messages:
    70
    Likes Received:
    11
    Trophy Points:
    19
    I was really just trying to replace the evaporator for an all-new Classic Auto Air a/c system. My plan was to replace the heater core while I had it apart. After trying to figure out how to get the evaporator out for about a half -hour, I figured I'd check online. It seems you can't remove the evaporator without removing the ENTIRE HVAC box assembly. So that new evaporator will be sitting in my house for years.
    #79
  20. milanorama

    milanorama Member

    Joined:
    Sep 1, 2013
    Messages:
    10
    Likes Received:
    1
    Trophy Points:
    14
    Wow thank god there aren't any razor blades in my toolbox. By the way, if you can't get to the back 2 screws on the heater box, I just pried it open with my hand, stabbed a right-angle o-ring pick in the side of the core and yanked, she came right out
    #80

Share This Page