Side air vents. Should each side blow equally?

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MisterB

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I'm referring to those floor side vents that just let in fresh air when you're driving at speed.

On my truck, the passenger side blows quite a bit more than the drivers side. Is that normal, or is something maybe plugged in there? Besides directly behind the flap that opens (which I have already checked), where else can I check?

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80BrownK10

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I'm referring to those floor side vents that just let in fresh air when you're driving at speed.

On my truck, the passenger side blows quite a bit more than the drivers side. Is that normal, or is something maybe plugged in there? Besides directly behind the flap that opens (which I have already checked), where else can I check?

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Don't know. I wish I had them. I have an AC cab. And I haven't fixed the AC yet. 100+ heat index is just hot driving .
 

Frankenchevy

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Try running a hose down the driver’s side of the cowl with the vent closed. Might let you know if you have leaf debris accumulated down there.
 

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Try running a hose down the driver’s side of the cowl with the vent closed. Might let you know if you have leaf debris accumulated down there.
Do you know where the inlet is for the vent, and then how or routes? I can't seem to find a schematic anywhere

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The openings in the top of the cowl in front of the windshield is where the air arrives from. See the plastic vented covers? Thats where the air enters the cowl for your vents.

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MisterB

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The openings in the top of the cowl in front of the windshield is where the air arrives from. See the plastic vented covers? Thats where the air enters the cowl for your vents.

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Cool. I recently replaced the screen and the rubber seal, and while I had it apart, I made sure it was clean down in there. Once it goes down the cowl, where does it go from there, before it ends up at the side floor vents?
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AuroraGirl

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I didnt realize the AC cabs DIDNT have those vents, or was it just misunderstanding? My non AC cab has a driver/passenger, and my 78 i guess i never checked
 

legopnuematic

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I didnt realize the AC cabs DIDNT have those vents, or was it just misunderstanding? My non AC cab has a driver/passenger, and my 78 i guess i never checked
All cabs have provisions for fresh air inlets, and kick panel vents, non a/c squares used the pull type vents, the a/c trucks use them in conjunction with vacuum pods to open or close depending on what setting it's on, a/c trucks also have a flapper under the cowl for recirculating in max a/c or defrost. So besides the firewall differences, any cab can be set up for a/c or no a/c.

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Cool. I recently replaced the screen and the rubber seal, and while I had it apart, I made sure it was clean down in there. Once it goes down the cowl, where does it go from there, before it ends up at the side floor vents?

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The rubber seal - one where the hood meets the cowl? Where did you get the new screen? I'm fixing to tear mine all apart and am collecting parts. Be my luck I'd have it all dissected and the part would be NLA or back ordered.

THX
 

MisterB

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The rubber seal - one where the hood meets the cowl? Where did you get the new screen? I'm fixing to tear mine all apart and am collecting parts. Be my luck I'd have it all dissected and the part would be NLA or back ordered.

THX
I got the cowl screen and the hood to cowl rubber seal from LMC

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Craig 85

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Here the best way to describe the flow. Fresh air goes in at the yellow arrow. It flows down the side of the cowl and out at the fan motor (round hole). From there, it follows the red arrow through the A/C or heater box and back into the cab at the rectangular hole.

If you have A/C and put it on max, there is a flap under the cowl left of the yellow arrow that mostly closes and the door in the passenger kick panel opens (photo #2) to recirculate air from inside the cab.

EDIT: I realized you probably meant the kick panel vents. I would guess the driver's side may have some debris in the cowl. I had a '64 Chevelle back in the day with no A/C and kick panel vents. Both vents flowed the same.

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MisterB

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Here the best way to describe the flow. Fresh air goes in at the yellow arrow. It flows down the side of the cowl and out at the fan motor (round hole). From there, it follows the red arrow through the A/C or heater box and back into the cab at the rectangular hole.

If you have A/C and put it on max, there is a flap under the cowl left of the yellow arrow that mostly closes and the door in the passenger kick panel opens (photo #2) to recirculate air from inside the cab.

EDIT: I realized you probably meant the kick panel vents. I would guess the driver's side may have some debris in the cowl. I had a '64 Chevelle back in the day with no A/C and kick panel vents. Both vents flowed the same.

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Correct. Kick panel vents. I can't find any explanation anywhere that shows how the air flows and ends up at the vents on the kick panel

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Craig 85

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Here's another picture. Air flows from the top of the cowl down the sides and to the red stars. Pretty simple. The vertical part of the cowl is double walled. If you take off the kick panel the vent door are attached to them. You would be able to reach your hand to where the red stars are.

One of the easiest way to see if you have debris in that area, is take a garden hose with high pressure nozzle and spray into the bottom of your fender just ahead of the door. I did this on my last truck, you wouldn't believe how many dead leaves and other crap came out. I actually added a hole to the bottom of the fender so I could clean the area easier and drain water/mud.

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MisterB

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Here's another picture. Air flows from the top of the cowl down the sides and to the red stars. Pretty simple. The vertical part of the cowl is double walled. If you take off the kick panel the vent door are attached to them. You would be able to reach your hand to where the red stars are.

One of the easiest way to see if you have debris in that area, is take a garden hose with high pressure nozzle and spray into the bottom of your fender just ahead of the door. I did this on my last truck, you wouldn't believe how many dead leaves and other crap came out. I actually added a hole to the bottom of the fender so I could clean the area easier and drain water/mud.

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Awesome info. Thanks!

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I bought a pair of these from Johnny Craigslist only to be let down that they couldn't work in my truck (AC cab)
 

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