heater fan - always on?

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byproxy

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thanks gents!!

so just to confirm 1low4x4, this fix would be for the non-ac rigs right?

Easy fix for that is to push the upper tab down then plug the connector back in. This keeps the damn the damn blower from running all the time and burning up. Still works when you want it to and only then.

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byproxy

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so is this the plug? if so, mine does not appear to have the prong bent down in the previous pic/post. am i not looking in the right place??
 

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89Suburban

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Ahh you have the heat only setup nice. :popcorn:
 

Rusty Nail

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I found this thread BECAUSE my fan runs 100% of the time Key On.

No.

This is 100% unacceptable.
When daddy says off, he means OFF.

Why the pictures regarding "bent prong" are no good?
Grr. WHAT PRONG?!
I will bend it! At what cost?
Grrr!

How to best fix? Because grr.

Jerry knows this answer @chengny .
 

74 Shortbed

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The idea behind that was to keep moisture out of the ductwork so you don't get mildew build up.
 

78C10BigTen

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Mine runs all the time key on too. Even in the off position
 

bucket

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That's just how it was then.
 

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It was called Astro-Ventalation in the cars. An attempt to prevent CO poisoning. Sometime in the 80's the Off position did start turning the fan off in the cars. Not sure on the Squares.
My '78 Impala fan ran all the time, but it had an added feature. As the fan immediately blowing at very low temperatures (close to 0F) feels very uncomfortable, the was a little, round thermostat that plugged into the back of the control head that opened the low speed circuit until the interior warmed sufficiently. You could switch to the other 3a speeds as desired.
My '78 Square doesn't have this feature or the provision for it.
 

bucket

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It was called Astro-Ventalation in the cars. An attempt to prevent CO poisoning. Sometime in the 80's the Off position did start turning the fan off in the cars. Not sure on the Squares.
My '78 Impala fan ran all the time, but it had an added feature. As the fan immediately blowing at very low temperatures (close to 0F) feels very uncomfortable, the was a little, round thermostat that plugged into the back of the control head that opened the low speed circuit until the interior warmed sufficiently. You could switch to the other 3a speeds as desired.
My '78 Square doesn't have this feature or the provision for it.

My '69 and '70 Impalas have the Astro Ventilation. It was a new feature for '69 as it replaced the wing windows. The cars had dash vents on each side even if no AC. There was a second knob on the kick panel that you would pull out and outside air would flow through the dash vent. You can have air flow through the kick panel, or the dash, or both. The blower on those cars doesn't run all the time.
 
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Rusty Nail

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Are you dudes trying to tell me (in so many words) that the fan running 100% of the time KEY ON is merely an accepted occurrence within this here msb?
The mostest epicest msb about square body trucks on the whole of the innerwebz and you motherfuckers just take it? Do I understand correctly?

One guy up ere talking about bendin prongs and I am about that, man, but he can't post a pic!

Omg while i'm gettin agitated, i might as well ask what you dudes know about making a 9/16, 350.
Because asking you all engine questions pisses me off too. :D:D:D:893Chainsaw-Smilie-
For some ******* reason I keep thinkin somebody in here should know about building motors. Lol motors. My knowledge is too limited.about that.still.

I'm tellin you right now now that MY truck is NOT allowed to run the blower all the time.

****.THAT.
Zero tolerance.

;)
 
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Honky Kong jr

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Are you dudes trying to tell me (in so many words) that the fan running 100% of the time KEY ON is merely an accepted occourance within this here msb?
The mostest epicest msb about square body trucks on the whole of the itnerwebz and you motherfuckers just take it? Do I understand correctly?

One guy up ere talking about bendin prongs and I am about that man, but he can't figure out how to post a pic!

Omg while i'm gettin agitated, i might as well ask what you dudes know about making a 9/16, 350.
Because asking you all engine questions pisses me off too. :D:D:D:893Chainsaw-Smilie-
For some ******* reason I keep thinkin somebody in here should know about building motors. My knowledge is too limited.about that.

I'm tellin you right now now that MY truck is NOT allowed to run the blower all the time.

****.THAT.
Zero tolerance.

;)
Lol my 87s don’t I need full power for cranking lol
 

CorvairGeek

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My '69 and '70 Impalas have the Astro Ventilation. It was a new feature for '69 as it replaced the wing windows. The cars had dash vents on each side even if no AC. There was a second knob on the kick panel that you would pull out and outside air would flow through the dash vent. You can have air flow through the kick panel, or the dash, or both. The blower on those cars doesn't run all the time.

I stand corrected :)
I had genuinely thought it was a part of the AV package.
 
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bucket

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Are you dudes trying to tell me (in so many words) that the fan running 100% of the time KEY ON is merely an accepted occourance within this here msb?
The mostest epicest msb about square body trucks on the whole of the itnerwebz and you motherfuckers just take it? Do I understand correctly?

One guy up ere talking about bendin prongs and I am about that man, but he can't figure out how to post a pic!

Omg while i'm gettin agitated, i might as well ask what you dudes know about making a 9/16, 350.
Because asking you all engine questions pisses me off too. :D:D:D:893Chainsaw-Smilie-
For some ******* reason I keep thinkin somebody in here should know about building motors. My knowledge is too limited.about that.

I'm tellin you right now now that MY truck is NOT allowed to run the blower all the time.

****.THAT.
Zero tolerance.

;)

It's how GM designed it. It's good enough for me so I leave it be. Honestly, I don't give a rat's ass if the blower runs at a low speed all the time. Obviously though, it bugs you :)
 

smoothandlow84

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I think the reason for the constantly on fan was to always allow fresh air into the cabin for recirculation and more importantly rid the cabin of exhaust fumes. I doubt that the GM engineers were concerned with keeping dust out. Thats a seriously funny theory though...lol



If by a slim...really slim chance that the GM engineers were in fact concerned with dust in the cab, it would make more sense to engineer better door seals. It is called a "fresh air vent" which by definition draws outside air in the cab. If its dusty outside...why design a system that draws in outside air ?



ANYWHOO...on a serious note to the o.p. YES the fan runs all of the time unless you bypass the system as it was originally designed and cut power to the blower fan. Most people, myself included also install an inline shutoff valve into the heater hose. When the inline valve is closed, it prevents antifreeze from circulating through the heater core. Since the fan is constantly on, without the inline valve, hot air will blow into the cab. In the winter time I open the valve and have heat. This modification is also helpfull if the heater core takes a **** and leaks into the cab.
 
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smoothandlow84

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It's how GM designed it. It's good enough for me so I leave it be. Honestly, I don't give a rat's ass if the blower runs at a low speed all the time. Obviously though, it bugs you :)
Geez....ya think?....lol
 

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