85 Heater Core=Cut Box To Remove?

[5spd85GT]

I have been all over the Internet and have seen no mention of simply cutting through the box surrounding the heater core to replace it, rather than remove the dash. I had the job done on my '85 GT many years ago (early 1996) by a guy who apparently did this method sort of half-way, i.e. there is a piece (approx. the width of the core and about 1.5 inches high) cut from the front of the box and apparently he loosened things up just enough to pry up the top cover (broke it actually on the back side and that was sealed with RTV along the seam) and slide the new one in, and then cover the hole with RTV. Well, this has had a slow leak for years (anti-freeze smell in car, film on windows, mysterious slowly disappearing fluid from radiator, and most recently fog out the vents) until this weekend when the anti-freeze is literally poring out the AC pee hole right onto the exhaust (yeah, not hard to find that leak)! I was able to remove the wonderfully located 5/16 screw at the top of the core cover and remove it (as I said, the guy had pried it up and broken it for removal years ago), so the question is, why not just cut down the front of the box the rest of the way to allow access to the old core and slide the new one in? Afterwards, a little J.B. weld and some more RTV to seal things up. It seems entirely too simple (versus taking out the entire dash), so who can give a little feedback to this idea?

[Zap's 85 GT]

I thought about doing this on mine when I replaced the core a few years back. The only way to do it right is to remove the dash anyway to make nice cuts. It would only speed up future replacements in my honest opinion. By the time I tore it all apart I didnt want to mess with it any more then I needed to and just replaced the heater core and reassembled it all. Doing the cutting and gluing would have added at least another hour and didnt want more hastle then I allready had.

[roller4v]

You really need to get the box out where you can look at it and make sure the heater core fits in correctly. If it is not place in exactly right it can bind causing the seems to break prematurely.

It is a royal pain to swap but its worth it to do it correctly and not hack up the box.

If I were looking to buy a car and found out the box had been cut up i'd immediatly start thinkin' about offering less money if I didn't just walk away. No telling what other short cuts had been done to the car over the years.

my 2 cents worth.
Steve

[5spd85GT]

Thing is, I don't really have too much in the way. The Dremel fits up through the glove box hole with loads of room to spare. Since I will have to clean out the core box anyway, any cutting flash will come out then.
I am a little nervous about proceeding without confirmation from someone else having performed this before, but that didn't stop me from rebuilding the unrebuildable Optispark on our former( oh, you know I sold that S.O.B.) 1994 Formula Firebird LT-1. I had to make that up as I went along (can tell you how to rebuild a hide-away headlight gear with J.B. Weld too, versus $250 for a new motor), with much research of course, and my method certainly wasn't in any manual anywhere, but the car ran like a spotted ape afterwards (I mean that in a good way...) and I saved hundreds (literally!, the cheapest part quote was $549.00) of dollars. I had loads of people tell me that wouldn't / couldn't work, but it did and it ran better than the previous 4 that were installed under warranty while we owned it (in fairness, I did modify it to '95 specs which may have helped).
That's not to say that anyone replying here about having to remove the entire dash is wrong, just that perhaps this cutting alternative has not been considered by many others before
I just want to save the labor and standing on my head time (yeah the cutting will require some, but just in one spot).
Also, what has anyone else used to seat the core in the box? I have read that you should remove all the factory goop and put in a layer of RTV to cushion the core.

[futurexdesign]

I cut the top of the box on mine then removed the 2 front heatercore access screws to get access to mine, you then have to remove some of the 'lip' once you get your now cut access cover off because of how the heatercore sits in the box (slanted).

this is how many 'nonpurests' do it (or so im told) simply because it saves time.

Kevin

[5spd85GT]

I am assuming your car is a different year model or has heat only, as mine does not have the screws in the front cover that you describe. I believe I know what you mean about the lip though. Could you go into a little more detail about what you did / faced on your repair?
To address another reply, I have been driving the car since '89 and never intend to sell it (you wouldn't sell your children would you? Well, okay, that is a loaded question for some...), so no worries about someone else not approving of my repair methods. I'm sure some purists would freak if they knew I was running a Cadillac application accessory belt because it fits perfectly when you have no smog pump (or any smog equipment at all for that matter :D ). Believe it or not, I still have the factory (possessed) premium sound tape deck and speakers in the car. Yes, they sound like crap, but that's a repair for later (the exhaust note sounds so good :lol:) .

[Freejack]

You may want to search around over on turboford.org. I believe a couple people there have done that to avoid dropping the fan housing.

This is one of those time when you are glad to be without A/C

Jake

[futurexdesign]

my car is an 86 capri with AC, i imagin you dont have the dash droped thats why you wont see the 2 screws i am refering to (they go in from the top).

Its a PITA but it is easiest just to drop the wheel, remove the 5 or so bolts holding the dash up and lay the whole thing onto the front seats. From there cut the access cover and yank it out.

Kevin
2P3Capri

[5spd85GT]

I thought you meant screws on the front, like a heat only car's access panel, my mistake. I did have to remove one 5/16" from the top, just shy of being center of the dash and was able to remove the "lid" on mine. As I said before though, the 'ole boy had already broken the backside years ago, so it didn't come off in the usual (PITA) way. Biggest PITA so far has been disconnecting the heater hoses under the hood :x . I almost cut the larger one before taking a frustration break and finally getting it off.
I did start the cutting last night, and really came to appreciate how poorly designed this thing is. Why in the world would Ford not have put an access panel on the front for A/C cars. Yeah, yeah, I know that question just opens up a whole new can of worms, but really how stupid was that.
I thought I had the cut finished (and as my Dremel battery was starting to fade I was glad) and then I discovered that this thing is double walled :evil: . Yes, I understand that it probably serves an insulating purpose, though I refuse to give Ford credit for that much thought. Anyway, I'll continue with a fresh charge tonight weather willing.
I still have not had any real feedback on seating the core, i.e. in a bed / layer of, I assume cured, RTV for cushoining, etc. Any thoughts on this or another product to use?

[Zap's 85 GT]

Its not just Ford. Many many other car companies heater boxes are built like this with little to no acess to the heater core without major disassembly.

[79 cobra]

I never cut anything .
When I removed the front cover screws , I used the handles
of the screwdrivers on the sides of the cover .
I pushed the handles towards the firewall .
It opened like a clam .
That gave me more than enough room to work .

The only screw up I did was , when I dropped the dash ,
I scratched the clock face on my center console .
Its just a little scratch , but I notice it .
Put a rag over it .

[jazzcat2001]

cut what box? the glove box to get it out? im in desperate need of replacing mine and this seems like an easy fix to pull it off

[5spd85GT]

Okay campers, just a small update. Only had a short time to work on it last night,and...ran into a snag. I was able to remove the remaining material that will allow the core to slide up and out freely, but I miscalcualted the room / clearance (i.e. length) to pivot the core out. Okay, the A/C vent ducting is in the way and cannot be pushed upward enough to allow clearance. It is slight on the left (facing the dash) and a little more significant on the right. This is blocking the upper most corners of the core. Obviously (or maybe not so), there is no easy way to loosen anything to allow clearance (where is it going to go, no room). I am noodling with this and hate to say it again, but one could cut the sections of ducting with a Dremel disk to clear the core and then seal them back with ducting tape, or something similar. I'm talking about cutting a section to provide clearance, not cut the duct in two. Looks as if the right hand cut would be diamond shape (especially if it were laid flat) and the left would be similar, but much smaller. Ideally, this would also allow for a quick (well...) change when this needs to be done again (you all know it will).
Hmm, wonder how many purists just had the eyes roll back in their heads 8O :roll: :lol: ? What's that? Yes, it is possible that I would already have finished the job by doing it the looooonnngggg way. Doubt it though. We have rain in the forecast for the next few days, so I probably won't be able to get back on it until Sunday.
I did notice (with my fingers) the spongy foam underneath the core (saturated in fluid :? ), but without being able to stick a mirror in there to look around, I'm not sure about where the factory placed their seating goop for the core. Anybody, anybody?

[79 cobra]

Try this link www.netcom.com/~skent/mustang/1990/heater_core/hcore.html

I hope this works .
I went on google typed in mustang heater core removal .
I picked the first sight listed .
They show pics , and give instructions .


Good Luck

[5spd85GT]

Yep, first one I found too.

[Zap's 85 GT]

Rain, Ha! I changed my heater core in England. 8 hours of getting rained on while I changed out mine. Had to do what I had to do.

[5spd85GT]

Mmm, mmmhmm. I don't reckon I wanna finish tinkerin' around with it thet bad. Reckon I've been borrowin' a truck to go back and forth and whatnot if I get the notion go sommers. Don't reckon I wanna be out in the rain nowheres, mmm. Reckon I might go out in the rain if they can spare 4 or 5 more cans of thet potted meat down at Hoochie's Dollar Store, mmmhmmm. Ite then.

[white1983GT]

Slingblade, ahhhhh and some of us are purty people

[5spd85GT]

Reckon I'm a gonna have ta get used to lookin' at 'em. Reckon I'm gonna have ta get used to 'em a lookin' at me too, mmm. Ite then, mmm.

[Anonymous]

When I replaced the heater on my 85 (with AC) I was able to do it all without cutting anything,breaking anything, or dropping the dash. It was a pain in the butt but I managed to do it in an afternoon. It's not something I want to do again anytime soon and won't be doing since I ditched the whole heater now!!

[5spd85GT]

Nitrousdave, how in the world did you have room to get the old core out, much less install the new one without either cutting or dropping?
I want your shop manual (sounds better than the one I'm making up as I go along). Could you give some detail on the procedure you followed, as I have not restarted the project due to the weather, so you may still save me some time. [/i]

[Anonymous]

I didn't use any manual when I did it. It's been like 5-6 years since I did it so this may or may not be exactly how I did it. I believe for some reason I unbolted the blower motor section from the rest of the unit. I also think I unbolted the whole unit from the ducting and the firewall so that I could slide it back and down so I'd have more room. If I remember right it wasn't really necessaery to unbolt the blower motor though. It's also possible that I might have loosened the lower part of the dash, but I'm not positive on that. Sorry I can't be of more help, it's just been too long to remember exactly how I did it.

[5spd85GT]

No, I didn't die, I've just been very tied up lately, soooo here is the rest of the story. Once I had an afternoon break from the monsoon season where I could get back to the car, I decided not to cut anything else and see if I could drop the dash enough to access the heater core through the amount of opening I had i.e. the piece that was already broken / cut from when the guy did this for me years ago and the amount I had removed below this. Long story short, I still hate whomever engineered this set-up, but now I dislike the manual-writing guys also. This is not a 7-8 hour repair (as the chorus in the background says "I told you so"). If you are in any form or fashion mechanically inclined and know how to improvise your tools (or just already have the perfect ones to fit everything) then you can remove the console and drop the dash in, oh, maybe an hour without rushing too much. I did use a pair of vise grips and a (trying to remember) 9/32 small socket to remove the dash top screws, between the glass and the dash top (and yes that little one in the middle can hold up the entire dash :) ). Oh, and have that stub Phillips head screwdriver handy as well. The other funky bolt would be the one you access after dropping the steering column. My manual was a little vague there, and I didn't see it the first evening in the dying light, but found it far back in there the next day (10 mm deep socket with extension helps).
Now, here is where my repair did go much more quickly than others: because I could access the heater core with some of the front of the box housing removed and about half the lid (up to just before it tucks under windshield surround area) removed, I could hold the dash down and slide the old heater core out very easily. It is not necessary to drop the heater / evaporator unit (with all the ensuing issues), just bite the bullet and cut or break the stupid box lid and save precious moments of your life for more worthwhile pursuits...really, no one will ever see this and if they do, they are changing the heater core and will thank you later. Now, to install the new one I ran into a couple of learning curves: the "sticky tape" (looks like a tar fruit roll-up with roofing shingle specks in it) I used to line the heater core box housing to rest / cushion the new core on likes to stick to your fingers instead of the box (plastic, go figure), so leave the white tape paper on and apply pressure along this. Also, I used a razor to cut it into thin strips to fit the box dimensions. The core; however, grabbed unto the strip I put on the passenger side bottom and proceeded to ball-up, obviously sticking the core right there. I just left that side off and it slid into position up to the firewall opening. Great...except I had left the little rubber protective end caps on the new core and they will not go through the opening. Third times the charm, and it slid right through and seated perfectly. Also, the heater flapper door control arm needs to be held down to keep it from ripping a hole in the bottom of your new core. I simply pushed it down and tied a string around the end and tied the other end off to the brace on the front of the assembly. I cut a piece of flat, black heavy plastic that came off of who knows what that my dad had made into an ice scraper (or maybe it already was one?) out in his garage and rat tail filed this to fit in the hole the guy left when he replace the core years ago. Yes, there were still some little gaps, but these filled in easily when I siliconed the piece I cut off the front and the lid top back onto the housing. Yes, it had (umm, still has just faintly when you first activate the fan) a little silicone odor for a few days, but that’s a heck of an improvement over the anti-freeze stink (silicone = the sweet smell of success :lol: ).
On the firewall side (under the hood) I had to come up with something to block the hole off (removed most of the old silicone blob in the removal of the old core). I cut a piece of black plastic flower bed edging (the flexible stuff that comes in 20 foot rolls) to fit the opening and cut two holes in this to fit the inlet / outlet necks through. I built up a good surrounding of black silicone (filling up the area pretty much), and then put the plastic piece (after the silicone had cured about ten minutes) on which even gave it a very finished off look, and sealed up nicely.
In all actuality, the two single items that took me the longest were: disconnecting the heater core lines under the hood (man were they ever on there!), and, embarrassingly enough, getting the stupid glove box back on to my satisfaction. Apparently, as I was removing things, I didn’t notice a minute difference in these two screws (first two I removed on the whole repair, last two to go back on) and I had heck getting the two screws I had left (that’s right, no left overs) to fit (a hair to large). I found one of them holding the dash pad on, but just made the other one work, but still it was just stupid how I couldn’t get the thing shut the way I wanted.
Are you still awake? Figured most folks would have quit reading long before this, hope not though as I feel the couple of tips I have imparted here will help someone. Now, when I have to replace this heater core (it’s a Ford folks, you know I will…well that and I‘ll never sell her…) I should be able to do it in record time because I can easily take the lid and front off my heater core box for easy access.

[v8only]

Nitrousdave, how in the world did you have room to get the old core out, much less install the new one without either cutting or dropping?
I want your shop manual (sounds better than the one I'm making up as I go along). Could you give some detail on the procedure you followed, as I have not restarted the project due to the weather, so you may still save me some time. [/i]

My brother and father have done this twice now, and have successfully removed the heater core on an a/c equipped car without cutting anything. It is a bitch for clearance, but it can be done. maybe corey 50 proof will chime in.

[Coupester]

My brother and father have done this twice now, and have successfully removed the heater core on an a/c equipped car without cutting anything. It is a bitch for clearance, but it can be done. maybe corey 50 proof will chime in.

EXACTLY. I ain't no purist goddamnit! But I can't f*&kin stand when someone gets their hands on a dremel and goes hog-wild ****er riggin these cars, it's just a shame.

That being said, I did what v8only did; remove the dash, and unbolt the heater box from the firewall (in the engine bay), and pull it back far enough to give you access to remove the 4, 5/16" bolts that hold the heater lid onto the heater box. And yes, there is enough room to work, even with the a/c still connected. I did not disconnect any a/c whatsoever, and this morning I used my ice cold a/c (it's 75* here in Cali), and when the sun goes down I'll use my heat as well.

Chris

[50 Proof]

first of all, don't short cut this. Your shortcuts are taking you longer then it would take to do it right. I've done 2 heater cores so far on two different mustangs, and it can be done without cutting anything.
Pop open the hood. You'll see your A/C (black)canister on the firewall on the passenger side of the car. There are two nuts on either side that hold it onto 2 studs coming out of the firewall. Remove these two nuts. Pry the a/c canister away from the firewall as possible. You'll see two more nuts behind the a/c canister bracket. Remove these other two nuts. So looking under the hood, you'll see, nuts, a/c canister bracket, 2 more nuts, and then the firewall(in that order going towards the firewall), all on the same two studs. Go inside the car. Pry the heater core box out and down as much as possible. You'll be able to clearance enough room(barely, but possible with the right tools), to remove all four bolts on top of the heater core box. Slide the lid off and insert the new heater core and the heater core lid at the same time. There is absolutely NO NEED to cut anything at all. I can't believe anyone would even think about slicing open the side of your heater core box. If I saw such a butcher job on a car that I was thinking of buying, i'd walk away from that car without any second thoughts.

[50 Proof]

http://www.corral.net/forums/showthread.php?s=&threadid=177981&highlight=heater+core

a very useful article. I know it's on another board, but it'll help you guys out a lot.

[mikejb]

I have done this 3 times in my 82. Here is my dremel cut on the box. I used ultra blue to seal it back up. http://home.comcast.net/~mike82gt/heatercore/82dash1.jpg

[v8only]

There has been so much talk about this recently that I thought I could offer a little more insight.

I have the dash out of my 86 vert already. I have an oem ford heater core waiting to go that was just purchased. My box has never been apart, and the car has factory a/c.

I will probably be installing it weekend after this. Keep a lookout, as I'll take a TON of pictures, and show everyone exactly what is involved in removing the heater core without cutting, so that you can make up your own minds when it comes to it which path you want to take. My father is helping me do this, and This is the third fox mustang he has done within 6 months or so, so he has gotten quite good at it!! I do feel sorry for him though, as everytime he thinks he has replaced his last heater core, Corey and I wind up with another mustang that needs it too