Engine Perplexing issue with heat ...

[MrPerfect2]

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

 

[MrPerfect2]

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]

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

 

[Olivethefet]

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]

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!

Mine got very difficult to turn a good while back (temp). A new cable makes it smooth as silk.

 

[MrPerfect2]

I need to check the temperature door - is that hard to get to?

 

[Wayne Waldrep]

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]

how hard is it to change temp cable

 

[Wayne Waldrep]

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]

Thanks Wayne !

 

[Decipha]

Id highly recommend adding a grounding strap to the core as well. I have seen many new ones fail due to electrolysis.