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What is this thing-part of heating system in engine bay

  • Thread starter Thread starter monk302
  • Start date Start date Feb 12, 2006

monk302

Founding Member
Apr 18, 2001
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New Jersey
Feb 12, 2006
#1
  • Feb 12, 2006
  • #1
Can anyone tell me what this thing is? It is my engine bay, I am putting in an EFI setup and trying to simplify my engine bay. All I know is this thing is ugly, and has a small tube running back through the firewall. Is it necessary?

View attachment Firewall-part2.bmp
 
6

66HertzClone

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Aug 24, 2004
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Central New Jersey
Feb 13, 2006
#2
  • Feb 13, 2006
  • #2
That is the heater control valve. When you use the temp selector on the dashboard to increase or decrease the heat in the car, that valve adjusts the flow of coolant thru the heater core. If you intend to have heat in the car it certainly would be nice to be able to adjust it to your comfort. If you eliminated it your two choices would be, no heat or high heat all the time. There are manual valves made that have a valve that you could open and close manually, however this would be mounted on the engine, not very convenient to use.
 

Tim65GT

Active Member
Feb 24, 2004
1,149
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West Texas
Feb 13, 2006
#3
  • Feb 13, 2006
  • #3
Not a very good pic, but looks like a vacuum motor to turn the flow of coolant to the heater on-off.
 
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jbuening

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Feb 13, 2006
#4
  • Feb 13, 2006
  • #4
Does your car have A/C? I was always told that when you turn on your A/C, this valve shuts off the coolant into the heater core. This keeps your interior cool and prevents hot air near the passenger's feet in the summer
 

Edbert

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Jul 13, 2002
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Feb 13, 2006
#5
  • Feb 13, 2006
  • #5
I thought those only came on AC equipped cars
 
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jbuening

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#6
  • Feb 13, 2006
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Edbert said:
I thought those only came on AC equipped cars
Click to expand...

My thoughts exactly
 

wild70stang

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Nov 11, 2005
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Feb 13, 2006
#7
  • Feb 13, 2006
  • #7
I have one of those on my factory A/C car. I was told that they came with all cars, since all cars originally came with a heater core.
 

monk302

Founding Member
Apr 18, 2001
742
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New Jersey
Feb 13, 2006
#8
  • Feb 13, 2006
  • #8
Actually my car was an air conditioned car. No longer though. I removed the condenser a while back. Should I leave it on or take it off? I don't use my air conditioner any more.
 
P

Protowrxs

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Jul 20, 2005
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Oklahoma
Feb 13, 2006
#9
  • Feb 13, 2006
  • #9
I would think you should be able to remove it without issues. I don't thin it is a modulated valve is it? Just on/off.

I had a manual valve on mine ages ago just to keep the heat out of the interior in the summer but it did not have one from the factory (non A/C).

I'm curious how this might work with EFI since the EFI intake I have has the engine coolant temp sensor in line with the heater core hose/hardline.

I would think if this is turned off that the sensor would not be able to read the correct engine temp??

Oh yeah, it *IS* ugly

-Stephen
 

monk302

Founding Member
Apr 18, 2001
742
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New Jersey
Feb 13, 2006
#10
  • Feb 13, 2006
  • #10
Let me try this again for a better picture. Look at this freakin rats nest of coolant hoses.
 

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J

jbuening

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Feb 13, 2006
#11
  • Feb 13, 2006
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monk302 said:
Actually my car was an air conditioned car. No longer though. I removed the condenser a while back. Should I leave it on or take it off? I don't use my air conditioner any more.
Click to expand...

Did you convert the switch to a heater only or does it have the A/C controls on it too? See on the 69/70 (what i'm most knowledgeable in), the non-a/c cars had cable only controls to switch from floor to vent and hot to cold (had electric for on/off though). The A/C cars had the floor to vent operated by vacuum, thus the vacuum line coming through the firewall and going to the heater control valve. Non A/C cars did not have any vacuum lines for the heater system so you obviously wouldn't have this valve. It is OK to leave it on, as it stays open when there is no vacuum applied. Not the prettiest thing, so if you want to tidy up your engine bay you might take it off. HTH
 

monk302

Founding Member
Apr 18, 2001
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New Jersey
Feb 13, 2006
#12
  • Feb 13, 2006
  • #12
jbuening said:
Did you convert the switch to a heater only or does it have the A/C controls on it too? See on the 69/70 (what i'm most knowledgeable in), the non-a/c cars had cable only controls to switch from floor to vent and hot to cold (had electric for on/off though). The A/C cars had the floor to vent operated by vacuum, thus the vacuum line coming through the firewall and going to the heater control valve. Non A/C cars did not have any vacuum lines for the heater system so you obviously wouldn't have this valve. It is OK to leave it on, as it stays open when there is no vacuum applied. Not the prettiest thing, so if you want to tidy up your engine bay you might take it off. HTH
Click to expand...

The switch has both heater and A/C controls. Though my controls operate an electric fan that pushes hot air into the cabin. Though even without the electric motor it is still dropping extremely hot air to the feet of both the driver and passenger. With your post above being said I think I may take it out. It is really an eyesore that doesn't seem to be too functional.
 
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