Got a at gap air handler & defrost duct I read the past post...

[Jwernatl]

I HAD an inch or so gap between the air handler duct & the defrost duct - while taking it apart, I thought to myself "dang good think Im in here, I can fix that.

look at pictures below .

Last night I was putting it back together - I mocked up a sleeve, inserted it and closed that gap.(I used a roll of rubber, some zip ties and a small amount of GORILLA DUCT TAPE) Lots of trial and error - took me about an hour.

Then tonight decided to search it.

I found a theory that the gap was intentional. From what I read, the A/C trucks had larger cfm blower motors. And, so the GM engineers needed to bleed off the mass amounts air (if only the defroster was selected).

So Im sitting here - contemplating - Do I undo what I did last night? will my defrost vents remind me of a rocket ship?


Think about it -

If I feel like there is to much air blowing thru the defrost, can I not turn the blower on low?

Anyone have a theory?
Anyone fill in that gap?
Anyone leave it?

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Hows your defroster?

 

[My78truck]

I thought I was the only one with this problem!!! My truck interior is in a state of complete overhaul, restoration, waterproofing. When putting the heater/AC ducts back in place, I saw that. Since I could not get the defroster venting to seat right, I just closed that gap up with foam and aluminium duct tape. In the past, my defrosters never blew a lot of air through them. Although I have not tired it yet, since closing that gap, I am sure that there should be a lot more air pushed through the defroster vents.

 

[75gmck25]

Mine also has a gap.

There is a set screw in the lower duct, and a plastic tab coming down from the upper. It looks like you would pull the ducts together and then put the screw through the tab to hold it in place. However, mine has never fully pulled together enough to not have a gap.

Bruce

 

[Grit dog]

Interesting. Thank you for sharing. As I have to reassemble that in the hopefully near future.

 

[SqBodyRestore]

After recently replacing the (original brass/copper) heater core, I found that I too have a gap at the heater box up to the defrost vent junction. Did anyone have any measurable results of leaving the gap, or sealing the gap??

 

[90Burb316]

I HAD an inch or so gap between the air handler duct & the defrost duct - while taking it apart, I thought to myself "dang good think Im in here, I can fix that.

look at pictures below .

Last night I was putting it back together - I mocked up a sleeve, inserted it and closed that gap.(I used a roll of rubber, some zip ties and a small amount of GORILLA DUCT TAPE) Lots of trial and error - took me about an hour.

Then tonight decided to search it.

I found a theory that the gap was intentional. From what I read, the A/C trucks had larger cfm blower motors. And, so the GM engineers needed to bleed off the mass amounts air (if only the defroster was selected).

So Im sitting here - contemplating - Do I undo what I did last night? will my defrost vents remind me of a rocket ship?


Think about it -

If I feel like there is to much air blowing thru the defrost, can I not turn the blower on low?

Anyone have a theory?
Anyone fill in that gap?
Anyone leave it?

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

Hows your defroster?

Personally, I think it should be sealed.
Did you end up leaving it sealed? If so, how does it work? Mine has lots of gap and everything leaks like a sieve. In really cold weather the cab of my Burb gets too hot while the defrost doesn't get enough heat because air just bleeds all over. However, I believe I also have issues with the door in the air handler not sealing/closing all the way too. It is a project on the back burner for now but I want a plan once I finally get to trying to fix it.