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  • 1974 - 1978 Mustang II Talk & Tech

lousy engineers....heater core

  • Thread starter Thread starter kcobra302
  • Start date Start date Oct 11, 2004

kcobra302

Founding Member
Mar 22, 2000
864
1
16
latham ny
Oct 11, 2004
#1
  • Oct 11, 2004
  • #1
well, i decided to torture myself and do my heater core. got the big ego cranking, figuring a couple of hours, maybe 3 at the most.

wrong........as usual. 2 1/2 hours just to get the thing out. hope to finish up on wed night. i know this was an "economy car" but man they could have made this a lot easier to do. i was thinking it couldn't be any worse than my 88 lx but i was wrong, again.

if anybody needs ac parts from under the dash let me know.
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
3
58
NE Ohio
Oct 11, 2004
#2
  • Oct 11, 2004
  • #2
kcobra302 said:
well, i decided to torture myself and do my heater core. got the big ego cranking, figuring a couple of hours, maybe 3 at the most.
Click to expand...





Been there, with a daily driver. Had to do it in the driveway with a flashlight.

No fun at all.
 

74ProII

Founding Member
Jul 23, 2000
194
1
17
Bremerton, WA, USA
Oct 11, 2004
#3
  • Oct 11, 2004
  • #3
I trhink we all been there done that. The core on my full size 82 wagon was no picnic either!
 

Eos

Oh Heather Oh yeah... I want your pink taco
Jun 13, 2003
734
3
0
oklahoma
Oct 11, 2004
#4
  • Oct 11, 2004
  • #4
I have learned there is NEVER a simple job with a mustang II. Like the time my ex boyf was putting my short thow in... took him like 2 hours or something because the hole that had been cut for the manual wasn't big enough.. and the bolts were the shifter bolt on to the tranny were a little too far back, he had to crawl under the car to like knock em loose or something. My tranny sets kinda crooked or something too.. lol
 
7

77sleeper

GO BUCS!
Founding Member
Oct 11, 1999
7,266
0
0
Napalm, AZ
Oct 12, 2004
#5
  • Oct 12, 2004
  • #5
I will bypass it and go without heat for months before I will ever change one again, GM has the heater core done right
 

kcobra302

Founding Member
Mar 22, 2000
864
1
16
latham ny
Oct 12, 2004
#6
  • Oct 12, 2004
  • #6
i thought about going the bypass route but this time of year and in the spring the windows fog up quick.

on a good note i have found the source of about 80% of my squeeks and rattles.
 

TheEvII

New Member
Sep 8, 2004
162
0
0
Lakemoor Il.
Oct 12, 2004
#7
  • Oct 12, 2004
  • #7
The worst part is that you can't change the heater hoses without removing the core. Most other cars have the hose connected at the firewall. Not the II. You have to take the core out to remove the hoses.
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
Founding Member
Jan 22, 2002
1,450
2
38
Pennsylvania
Oct 12, 2004
#8
  • Oct 12, 2004
  • #8
heater core

The VERY first thing I did when I got my car was to take off the dash and replace the heater core even though it did already work without leaking at the time but I had to be sure. I had taken two days of work off to do the job and just barely got it done in time. man, i remember those days.
 

Eos

Oh Heather Oh yeah... I want your pink taco
Jun 13, 2003
734
3
0
oklahoma
Oct 12, 2004
#9
  • Oct 12, 2004
  • #9
Mine went to the shop =)
 

cobra_2_76

Founding Member
Aug 24, 1999
201
0
0
Norwalk, Ohio
Oct 12, 2004
#10
  • Oct 12, 2004
  • #10
Amazing comments....remove two control cables, four bolts hold the casing to the firewall, one bolt under the dash for a support, remove the vent tube, defrost vent and floor vent and it falls out.

I don't know what your doing that makes it such a job, but when I followed the shop manual, which included taking pictures, I had it out in two hours.

Couple more hours cleaning, re-sealing and had it back in place in maybe two hours more. I took my time, pulled the dash top, glove box, and passenger bezel out.

I didn't bleed or scream, so I'm confused??? Now I don't have AC and I'm sure that adds some problems, but considering I did blow the core while running at 6,000 rpm at the end of the strip which made a real mess and finished off my original carpet, I was pleasantly surprised how easy it really was.

Dave
 

welder4956

20+ Year Stangneter
Nov 28, 2003
228
89
38
Birmingham, AL
Oct 12, 2004
#11
  • Oct 12, 2004
  • #11
TheEvII said:
The worst part is that you can't change the heater hoses without removing the core. Most other cars have the hose connected at the firewall. Not the II. You have to take the core out to remove the hoses.
Click to expand...

I have no trouble disconnecting my hoses from inside the engine compartment. Why is yours different?
 

kcobra302

Founding Member
Mar 22, 2000
864
1
16
latham ny
Oct 12, 2004
#12
  • Oct 12, 2004
  • #12
i had mine out in 2 1\2. the unit containing the ac and the heater core runs from the passenger side kick panel across the tranny tunnel to the gas pedal. then you need to deal with the ac ducts themselves. plus with the ac your not only messing with the heater core ends going thru the firewall you also have all the ac going thru the firewall in a totally different spot. oh don't forget the vacuum controls, the electrical connections, the control cables, rmoving the glove box, then there is a support for the dash that is in the way that runs from just behind the radio up to the base of the windshield.

i also had two guages mounted under the glove box, so they had to be removed.

i am sure there are people out there that could have done it quicker but i don't think i did to bad. i just think they could have done the design a little better. like making a door at the bottom of the unit so the only thing you had to do was remove the screws for the door and the hoses on the engine compartment. then it would literally fall out.
 
7

77sleeper

GO BUCS!
Founding Member
Oct 11, 1999
7,266
0
0
Napalm, AZ
Oct 12, 2004
#13
  • Oct 12, 2004
  • #13
cobra_2_76 said:
Now I don't have AC and I'm sure that adds some problems,
Click to expand...

ding ding ding we have a winner

it takes like 3x as long with AC
 

TheEvII

New Member
Sep 8, 2004
162
0
0
Lakemoor Il.
Oct 12, 2004
#14
  • Oct 12, 2004
  • #14
I have no trouble disconnecting my hoses from inside the engine compartment. Why is yours different
Click to expand...


Mine went straight into the firewall and had to be disconnected at the heater core. I probably wouldn't have changed the heater core if I could have changed the hoses without taking it out.

 

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notmundane

New Member
Oct 11, 2004
0
0
0
Oct 12, 2004
#15
  • Oct 12, 2004
  • #15
Use Mercedes coolant

Mercedes has a special antifreeze that is ph balanced (gold in color - fitting, since it costs a lot). I've been using it for years, and no more rust in the mix.

Also, I was once young and naive enough to tackle a heater core replacement on a 1974 Datsun B-210 - started 7 pm on a weekday and had to have it by 6 am to go to work the next day. Had to remove the driver's seat and hood to gain access, then completed job with flashlight at 4 am. 1 hour nap and it was off to work we go with driver's seat flopping around due to lost trac nuts and hood leaning up against by mobile home's front door.

I could no more fit under that tiny car's dash today than Godzilla. Yep, those were the days...
 

kcobra302

Founding Member
Mar 22, 2000
864
1
16
latham ny
Oct 14, 2004
#16
  • Oct 14, 2004
  • #16
finished in a little under 5 1/2 hours. i am kinda glad i did it. all the squeaks and rattles are finally gone. now just need to find the rest in the back of the car.

for those trying to save weight, the removal of ac exchanger,the ac ducts and misc pieces came in just shy of 14 lbs.
 
Z

zwhitr

Founding Member
Aug 26, 2001
847
0
16
Goldsboro, NC
Oct 14, 2004
#17
  • Oct 14, 2004
  • #17
kcobra302 said:
finished in a little under 5 1/2 hours. i am kinda glad i did it. all the squeaks and rattles are finally gone. now just need to find the rest in the back of the car.

for those trying to save weight, the removal of ac exchanger,the ac ducts and misc pieces came in just shy of 14 lbs.
Click to expand...

Now I will admit with the A/C unit it sux since the whole box has to be removed.


But I can get mine out in under and hour the trick is to remove the bolts that hold up the steering column lay it in the seat then remove the 2 bolts on top of the dash and the 2 bolts on the side pull the dash away from the firewall and your A/C box is in your face pull and drop works like a charm

3 times and counting

ps dont forget the brace bar that hold the dash at the radio location..

ps Evil I don't know why yours if diff hose clamps mounted on the out side in the engine bay one time I ended up breaking the solder joints replacing the hoses and ended up replacing the core also..
 
J

Johan

Member
Jun 12, 2003
81
0
6
Waldheim, LA
Oct 14, 2004
#18
  • Oct 14, 2004
  • #18
zwhitr said:
Now I will admit with the A/C unit it sux since the whole box has to be removed.
Click to expand...

The fox body was even worse. The box looks very similar in design, but instead of screws holding the top half to the bottom, the box is essentially welded into one piece.
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
3
58
NE Ohio
Oct 14, 2004
#19
  • Oct 14, 2004
  • #19
zwhitr said:
Now I will admit with the A/C unit it sux since the whole box has to be removed.
Click to expand...

That glosses over evacuating the freon, dealing with the AC plumbing and the expansion valve.

I've done both AC and non-AC boxes, I thought the non-AC box was a PITA .... little did I know how much harder the AC cars are.
 
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