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Topic: Any ideas on why my blower pushes air out the cowl?

in Forum: C3 Cooling and Heating Systems


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Any ideas on why my blower pushes air out the cowl? (1/6)
 9/5/23 11:52am
sdinino
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Rock Hill, SC - USA

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I noticed the other day that when my blower is on high, I get a strong blast of air out the cowl area. I would think air should go IN there, not out. Any thoughts on why? I did the C4 fan upgrade w spacer and that works great. I’m fairly sure my fresh air door actuator is functioning, but I’m double checking later. 

it bothers me because I want that air in the car, not out the cowl. Hoping for some input. 



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Re: Any ideas on why my blower pushes air out the cowl? (2/6)
 9/5/23 6:16pm
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My first thought is that perhaps there is a crack, or some other leak between the A/C plenum and the wiper/cowl area. Also, with the newer fan set-up, it's possible it is pushing enough air into the car that excess air could be flowing out the fresh air door up into the cowl area. That door is only closed with the A/C on full high/Max. Just some thoughts...



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Re: Any ideas on why my blower pushes air out the cowl? (3/6)
 9/6/23 7:47pm
sdinino
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Rock Hill, SC - USA

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Thanks for the ideas. I checked the fresh air door and the recirculate door actuators  with the vac pump, and both work as expected.

I guess it could be ‘extra’ air, since I am definitely getting air out the vents inside the car too… but I still can’t wrap my head around why I’m not feeling air being pulled in at the cowl. Where is all that air coming from? I should be able to find a place where there’s a draw, right? 

I know some guys seal up the door down by the kick panel so the system always function In recirculate mode which would solve this issue, but I kinda want it to work as designed. 



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Re: Any ideas on why my blower pushes air out the cowl? (4/6)
 9/6/23 8:05pm
F4GaryGold Member
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Grapevine, TX - USA

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sdinino said:

Thanks for the ideas. I checked the fresh air door and the recirculate door actuators  with the vac pump, and both work as expected.

I guess it could be ‘extra’ air, since I am definitely getting air out the vents inside the car too… but I still can’t wrap my head around why I’m not feeling air being pulled in at the cowl. Where is all that air coming from? I should be able to find a place where there’s a draw, right? 

I know some guys seal up the door down by the kick panel so the system always function In recirculate mode which would solve this issue, but I kinda want it to work as designed. 


In recirc mode, the door in the kickpanel is open.



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Re: Any ideas on why my blower pushes air out the cowl? (5/6)
 9/7/23 1:48pm
sdinino
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Rock Hill, SC - USA

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1977 White/Red


Joined: 8/2/2017
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F4Gary said:
sdinino said:

Thanks for the ideas. I checked the fresh air door and the recirculate door actuators  with the vac pump, and both work as expected.


In recirc mode, the door in the kickpanel is open.

At first I though this was incorrect, since both doors should get vac when set to Max. But when I checked the logic table diagram again, I noticed that the lower kick panel door is normally closed. Vacuum opens it. So I stand corrected. 

Checking around, seems that the reason given to seal it up is generally to prevent water intrusion. 

Anyway…

Next step is to get the engine back together enough to test what actually happens when set to Max with engine running. 



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Re: Any ideas on why my blower pushes air out the cowl? (6/6)
 9/7/23 2:00pm
F4GaryGold Member
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Grapevine, TX - USA

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If you need a/c, Max is the only setting you should be in with these marginal a/c systems.



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