Engine Replacing A Heater Core

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,388
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Kearney, NE
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

I bet it was a satisfying feeling to stab the part that made for all that work.
 
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Illuminator

Active Member
Nov 29, 1999
219
10
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So. Cal
It's about time I finally get around to doing mine....It's been well over 7 yrs since it went out, but the car was only used randomly, not I need it as a DD, and not gona be freezing or hanging out the window trying to see the road when the windows fog up. I don't recall but isn't there some kinda special crossover tube/pipe in the engine compartment the heater ties into?? I think mine was rusting thru and I might have tossed it when the core was bypassed. Thanks for the input....
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,388
3,091
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Kearney, NE
Yes there was a pair of metal tubes on the passenger side. If you pulled the pair, where did you put the temp sensor that plugged in there and what did you do about the little coolant line that runs from there to the EGR spacer?
 

Illuminator

Active Member
Nov 29, 1999
219
10
29
So. Cal
Yes there was a pair of metal tubes on the passenger side. If you pulled the pair, where did you put the temp sensor that plugged in there and what did you do about the little coolant line that runs from there to the EGR spacer?

That's a very good question...I will have to take a look and see, it's dark out already so will look in the am
 

Illuminator

Active Member
Nov 29, 1999
219
10
29
So. Cal
Yes there was a pair of metal tubes on the passenger side. If you pulled the pair, where did you put the temp sensor that plugged in there and what did you do about the little coolant line that runs from there to the EGR spacer?

Wow, I must really be getting old, it's still there under everything, just never noticed it.....lol What are your thoughts on those heater hoses with the restrictors built into them?? Supposedly the factory setup pushes too much coolant thru the heater core and eventually taxes it from what I read....is this true?
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,300
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In the garage
Wow, I must really be getting old, it's still there under everything, just never noticed it.....lol What are your thoughts on those heater hoses with the restrictors built into them?? Supposedly the factory setup pushes too much coolant thru the heater core and eventually taxes it from what I read....is this true?

Yep... here you go. It goes in the inlet hose.

Ford part #E7VY-18D358-A

or.... just use a cheapo 13mm 3/8" 6 point socket.

http://www.sears.com/craftsman-13mm-socket-6-pt/p-00943545000P?prdNo=1&blockNo=1&blockType=G1
 
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Illuminator

Active Member
Nov 29, 1999
219
10
29
So. Cal
It's the larger lower hose that comes off the intake.

Sorry if that seemed like a lame question, I was too involved trying to get the dash out.... which btw seems a bit different then the pix and intro to this thread....my big issue was the lower bolt on heater box(couldn't locate it well in the dark) and the various electronic "boxes" under the dash (1 at glovebox, other in left center) any idea what these are? Does anyone know if someone sells a kit for the box to rebuild with fresh foams/felts, etc?? I know they have em for the older stangs, like 70's because I used a few of em. Mine is fairly rotten with all the moisture that has been getting in there for years. I took box out today at work, (yes I'm driving w/o a dash) going to bring it in and take it apart tonight, see how nasty it is inside.
 

Doopy

New Member
Oct 31, 2013
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Tacoma, Washington
Hello all. Absolute newbie here. Trying to replace the heater core in my brother's '91 4-cylinder 'stang, with little to no experience in major automotive projects. Can't afford a mechanic, so I'm stuck doing it myself.I'm having incredible trouble getting the A/C disconnected so I can get the plastic housing for the heater core out where it's accessible. The tool I bought for the A/C line spring disconnect doesn't go in, using any of the available sizes. We found a Youtube workaround that substitutes a small steel band off a rubber hose constrictor for the disconnect tool. The band will not go in.I've heard legend in some of the tutorials about replacing the heater core without disconnecting the A/C lines. Anybody know how this is done? Feel free to use detailed instructions like you're talking to a six-year-old.