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Heater Core Help

  • Thread starter Thread starter MoatesGarage
  • Start date Start date Dec 10, 2008
M

MoatesGarage

New Member
May 11, 2004
38
0
0
Dec 10, 2008
#1
  • Dec 10, 2008
  • #1
Hey guys, got a 2001 Mustang GT here that is now on heater core number six in two years. The Ford Dealership was nice enough to say they weren't going to warranty it this time so I get to put in another one. They did say they'd cut me a deal at $800 and I'd have another one year warranty on it. They can't seem to say why this car CONSTANTLY blows heater cores, but until recently they said every 2001 has this problem. I bypassed the core until it got in to the teens here recently and thought now would be a good time to fix it. I called Steeda to see if they had a lower pressure radiator cap as I'm looking for anything that will keep this thing from pouring anti-freeze in to the cab...again.

Things I've done -

1. Tested negative for Electrolysis
2. Contacted Ford and they deny that there is a problem and it's obviously a modification I've made to the car. The car is stock. Their solution is to buy a new Ford and sell that one to someone else.
3. The core has been replaced but the hoses leading in to it never have so I ordered new ones of those for this go-round.

The dealership (and strangely Steeda) said this is an isolated incident and no one on earth has had to replace a heater core in a Mustang ever. Did Ford buy out Steeda and I didn't get the memo? Anyway...if somebody knows anything that can help me from doing this again in three to six months I'd appreciate it.
 

mustang_montana

Member
Jun 20, 2005
137
0
17
Dec 10, 2008
#2
  • Dec 10, 2008
  • #2
id get another heater core, i had good luck with the one i got from Latemodel Restoration Supply - Mustang Parts, Chevy Truck Parts & Dodge Challenger Parts. put mine in over 4 years ago, no problems.
 

96SCstang

New Member
Jul 22, 2006
228
0
0
novi, MI
Dec 10, 2008
#3
  • Dec 10, 2008
  • #3
ok...the only thing i can tell you is this. as a certified mechanic no car should ever have to do that many heater cores. there is a problem somewhere. i have an idea as to what it might be. there is supposed to be a restricter in the inlet side of the heater core hoses. it's a plastic piece shoved in the hose and held in place by a clamp around the hose. the water pumps on this motor are really powerful and at full throttle and high rpm's the flow is so strong that it actually blows the heater core. this is also a flaw of the heater core being so restrictive. check to see if you have this plastic piece and check back. i have a few other ideas but they are more complicated and this is an easy check. :SNSign:
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Dec 10, 2008
#4
  • Dec 10, 2008
  • #4
mine is fine but i replaced one in my buddies 04 when he had 50K on it
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Dec 10, 2008
#5
  • Dec 10, 2008
  • #5
i'll replace it for $600 for you!!
 

96SCstang

New Member
Jul 22, 2006
228
0
0
novi, MI
Dec 10, 2008
#6
  • Dec 10, 2008
  • #6
yea but he isnt asking who wants to replace it. he is asking why it has to KEEP being replaced. LOL
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Dec 10, 2008
#7
  • Dec 10, 2008
  • #7
i know....my guess would be too much pressure
 
P

poindexternasty

New Member
Apr 29, 2008
148
0
0
Dec 10, 2008
#8
  • Dec 10, 2008
  • #8
Could there possibly be a restriction somewhere else in the engine?
 
M

MoatesGarage

New Member
May 11, 2004
38
0
0
Dec 11, 2008
#9
  • Dec 11, 2008
  • #9
Well it has the factory hoses on it with those stupid clips. I just ordered a new set because I had read somewhere else online that they'd changed. The car has 85000 miles on it and I guess the problem started about 10k miles ago or so. I think the inlet hose was actually broken and that's why the last time they told me it was a heater core. The dealer was nice enough to say "good for you" when I told them they were about to charge me $800 for a hose. I replaced it with a $10 auto zone hose and about a week later it blew, then of course I learn about the restriction on the factory hose. So I guess I'm kindof an idiot there. But I replaced the radiator cap this time just in case it was holding too much pressure or something. The core I got at Auto Zone and it has a lifetime warranty...and it was a little less than half what the dealer wanted for a Ford one.

and as far as the rapid replacement....EVERY time we took it to the dealer they said this happens to every single 2001 Mustang, Explorer, Navigator and several others. He says its manufacturer problem and it's just something we'll have to do annually like everyone else. Yesterday it was like someone was sticking a hot knife to them as they changed their tune to "we've never had another mustang in here with a heater core. Must be something YOU are doing and this is for sure an isolated incident."
 
B

BobHyatt

New Member
Aug 7, 2007
378
1
0
Dec 11, 2008
#10
  • Dec 11, 2008
  • #10
obvious question

Thought I would ask, just to be sure... any chance the hoses were reversed? That could put the restriction on the down-stream side of the core, which raises pressure in the core rather than reducing it. You should be able to feel the restriction in one of the hoses. Disconnect at the heater core and crank engine with a bucket under that hose. Water should come _out_. If it comes out of the heater core, you just found your problem. The restriction is on the wrong side. This normally would not happen, but I have seen exactly one where apparently the owner mangled this himself. Note that just swapping hoses at the core doesn't cause this. They have to be swapped on the other end or else the restriction will still be on the pressure side where it should be.
 
M

MoatesGarage

New Member
May 11, 2004
38
0
0
Dec 11, 2008
#11
  • Dec 11, 2008
  • #11
Don't think they were reversed. Seems like that would be hard to do, but I guess I can check that out when we install the new ones.
 
S

Smokeurhonda

New Member
May 1, 2003
457
0
0
Maryland
Dec 11, 2008
#12
  • Dec 11, 2008
  • #12
WOW, I fuggin hate ford service. They are a bunch of liars. The foxbodies used to blow heater cores but this is the first I've heard on a newedge car. I would agree to look into the restrictor in the inlet hose/reversed hoses. Check that and hit us back.
 

flstang65

10 Year Member
Dec 6, 2007
1,484
135
94
SE Georgia
Dec 11, 2008
#13
  • Dec 11, 2008
  • #13
have the thermostat or cap on the reservoir bottle ever been replaced?
 
M

MoatesGarage

New Member
May 11, 2004
38
0
0
Dec 12, 2008
#14
  • Dec 12, 2008
  • #14
Nope, but we flushed out the plastic resevoir because it was full of junk. They also say it's been flushed every time it's been there, but...and I know this is hard to imagine at this point...they've been lying to me about flushing it.
 

flstang65

10 Year Member
Dec 6, 2007
1,484
135
94
SE Georgia
Dec 12, 2008
#15
  • Dec 12, 2008
  • #15
could the extra pressure from a faulty cap or thermostat be causing the blow outs? maybe replace the reservoir, cap and thermostat? I don't know, man...this is a good one.
 

Purerock Racing

New Member
Dec 2, 2008
2
0
1
Quartz Hill, CA
Mar 5, 2010
#16
  • Mar 5, 2010
  • #16
stupid question, but my heater core just started to leak (I smell anti freeze and the windsheild fogs up), so I want to bypass the heater. Is that a simple thing? I see the 2 hoses going into the firewall, do those have fittings on them or are those just hose clamped on and you can add another pc. of hose to bypass the heater core? My heater core lasted 174k miles!!! Not bad I guess.
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Mar 6, 2010
#17
  • Mar 6, 2010
  • #17
you can bypass it but i would just replace it. it's only about a 4-6 hour job
 
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