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Engine Perplexing issue with heat ...

  • Thread starter Thread starter MrPerfect2
  • Start date Start date Sep 12, 2019
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MrPerfect2

5 Year Member
Jul 23, 2019
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Washington DC
Sep 16, 2019
#21
  • Sep 16, 2019
  • #21
Got a new stock fan and heavy duty Haynes fan clutch - suction will hold paper all they way through A/C condenser at idle - it’s probably the inside of radiator clogged at certain areas - the water pump circulates hard but coolant may not flow through some areas
 
Reactions: General karthief

MrPerfect2

5 Year Member
Jul 23, 2019
308
54
48
Washington DC
Sep 16, 2019
#22
  • Sep 16, 2019
  • #22
The flap on heater core box is up when the fan is off - once I turn on fan the flap rotates to the down position and seals good - the temperature knob changes the air temp from cool to warm and does not effect the flap . Pushing the flap up does not effect the air temp - what is the flap for btw?
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
20+ Year Stangneter
Apr 14, 2003
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Cuba, AL
Sep 16, 2019
#23
  • Sep 16, 2019
  • #23


Look over this. It shows all the air paths (doors).
 
Reactions: Olivethefet

Olivethefet

I will own your nuts! LOL
5 Year Member
May 17, 2018
2,596
1,790
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Enterprise AL
Sep 16, 2019
#24
  • Sep 16, 2019
  • #24
Ok. So the cable actuates the door to control the temp. The vaccum controls the defrost, and cabin air recycle.

The cable must be stuck on my car. You cant turn the temperature adjustment knob. It's on the list to fix!
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
20+ Year Stangneter
Apr 14, 2003
1,338
659
143
Cuba, AL
Sep 16, 2019
#25
  • Sep 16, 2019
  • #25
Olivethefet said:
Ok. So the cable actuates the door to control the temp. The vaccum controls the defrost, and cabin air recycle.

The cable must be stuck on my car. You cant turn the temperature adjustment knob. It's on the list to fix!
Click to expand...
Mine got very difficult to turn a good while back (temp). A new cable makes it smooth as silk.
 

MrPerfect2

5 Year Member
Jul 23, 2019
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Washington DC
Sep 16, 2019
#26
  • Sep 16, 2019
  • #26
I need to check the temperature door - is that hard to get to?
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
20+ Year Stangneter
Apr 14, 2003
1,338
659
143
Cuba, AL
Sep 16, 2019
#27
  • Sep 16, 2019
  • #27
You don't actually get to it. What you can do is get someone to turn it from all the way hot to all the way cold. Have a flashlight there. Locate the end of the cable that attaches to the heater box (temp door). It should move the arm back and forth which moves the door. You can also hear the door when it touches both sides.
 

MrPerfect2

5 Year Member
Jul 23, 2019
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Washington DC
Sep 18, 2019
#28
  • Sep 18, 2019
  • #28
how hard is it to change temp cable
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
20+ Year Stangneter
Apr 14, 2003
1,338
659
143
Cuba, AL
Sep 18, 2019
#29
  • Sep 18, 2019
  • #29
Remove the hvac controls just enough to get to the cable end and remove it. Lean in the passenger door and follow the cable all the way to the attaching point on the heater box and remove it. Replace with the new cable. I hate under dash work but it's not hard at all. It's just cramped up in there but you can see both ends. The second time you do it will take 30 minutes.
 

MrPerfect2

5 Year Member
Jul 23, 2019
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48
Washington DC
Sep 18, 2019
#30
  • Sep 18, 2019
  • #30
Thanks Wayne !
 
Reactions: Wayne Waldrep

Decipha

Active Member
Aug 22, 2007
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New Orleans, LA
Sep 18, 2019
#31
  • Sep 18, 2019
  • #31
Id highly recommend adding a grounding strap to the core as well. I have seen many new ones fail due to electrolysis.
 
Reactions: General karthief
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