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A/C air flow



A few weeks ago we were talking about some folks having a low volume of air flow into the car with the a/c on full. What I found and would like to pass along is that mine was leaking air between the firewall and blower housing inside the engine compartment. After I slipped my hand up behind the blower housing and the right fender I could feel air blowing out from behind the housing where it attaches to the firewall. This was my missing air flow that should of been blowing in the car.
What I did to repair this was instead of taking it all apart was to buy some gray cord weatherstrip at Home Depot which is a strip of gray putty like material. I rolled it between my hands until it was about pencil thick in diameter and about 18" long. I then reached back behind the fender and stuffed it into the entire seam around the housing adding new lenghts until I had it all stuffed in the seam well. This sealed it up and about doubled the air flow into the car.
One thing of importance is to really clean the area first so the putty sticks to the firewall and housing. I did this with a spray bottle of Castrol super clean (be careful it will suck all the oil out of your skin). Just soak it down all around the housing area. I then did the same using soapy water in the spray bottle, and hosed it all off with the garden hose. Let it dry real good. I let mine dry over night and most of the next day. I also let the blower motor run for about 20 min after hosing it to blow out any water in the seam area.
Well to make a long story short it worked fine. Just clean it good and work the putty into the seam with your finger tips as best you can all the way around. Only took about 15 minutes to seal the seam.
Great news

Thanks for letting us know. That subject does come up from time to time. We will have to share this tech tip with others having the same problem.
looking in all the wrong places for air.

Hey resto I think you may have solved my problemo. For many moons I knew that somewhere out there was air. All my checking I never thought about it blowing out underneath and cooling my side pipes. After reading your post I went to the garage and surenuff, what do you think I found. Well it wasn't Easter eggs! You made my day. Those gaping gaps are just a sign of master craftsmanship I suppose. By the way does anybody know what the function of that metal tube is that is sticking up beside the blower motor? It blows out a lot of cold air. I was so pleased with finding those other air leaks that I will fix tomorrow that I forgot to check that tube. 1977 model.
Re: looking in all the wrong places for air.

iwannafly said:
Those gaping gaps are just a sign of master craftsmanship I suppose.

Not to mention the elderly age of our cars.

- Eric
Sealing up that seam should solve the problem. Also check around all other holes in the blower box. I found a few small leaks where a/c pipes went into the box and up top where there is a diamond shaped cover that screws down on top of the box. I guess those 25/30 year old seals just don't hold up like they should.
Hummmm . . . gotta go to the garage now . . . hope swmbo keeps my dinner warm . . .
Those leaks are also where the hot air comes into the passanger compartment.


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