AC/Heater Duct Inlet Gasket
 

I can't seem to find a replacement for the thick sponge rubber gasket that goes between the air handler/heater core unit and the under dash duct work. This is the square opening above the heater floor outlet, it has the two flapper valves in it and connects to the under dash duct work. It was about 1" thick spongy sticky rubber stuff.

Nothing in the Ames AC seal kit comes close .. which by the way is about the cheesiest bunch of cheap foam I've ever seen. Thinking of tossing it and ordering the raw materials and cutting them out myself. Stuff doesn't look like it would last two years in under hood conditions.

I got mine from Inline Tube or Parts Place. It was indeed cheesy. You might be better off making your own.

I used a roll of expandable foam insulation from Home Depot. Seals well and is way less messy than the original gunk.

Was there a seal between this whole interior AC/Heat unit and the inside of the firewall, or did it just seal against the inner firewall insulation?

I didn't see a seal in the assembly manual nor was there one when I removed the housing. I just placed it against the firewall insulation.

OK .... same here, I looked in the assembly manual and didn't see anything.
Thank you.

Another question.

I've got the gap seen below between the defrost air supply and the ducts leading up to the windshield. I can pull it down enough to get the screw in, and even in the same place as it was originally ... but there would still be at least a 1/4" gap there ... is that normal or was there something that wrapped this gap? Duct is properly clipped up at the top, and the AC/Heat box is of course in the right spot since it's bolted in.

https://forums.maxperformanceinc.com...0&d=1633600414

AC Heater Duct Inlet Gasket
 

I have the exact same issue with my car. So far the only solution that I'm going to use for now is to put weatherstrip wide enough to fill the gap around the area between the duct and AC Heater Box but if somebody replies to you with the correct fix please let me know.

Carousel72TRed

Every car I've ever had has had a slight gap there. The plastic does age and shrink a bit, but I believe the gap is intentional. Just pull it down slightly to screw it in and forget about it.

Weatherstrip on the roll, I’d contact it on as well.

Its normal. On the A/C and heater cars.

Yep I thought the gap might be intentional since there is no way those little ducts can carry the entire output of the blower.

AC/Heater Duct Inlet Gasket
 

Yes that seal set you ordered and I ordered from Ames is a disgrace. I am looking for a replacement foam seal for the upper and lower door area you are talking about. Also my ram air lower lower pan seal has deteriorated and material is flaking off from it. I only use it for show at car shows but it is my understanding original foam seals had some kind of semi sticky stuff applied to the seal which probably made the seal last for a much longer period of time. When you come up with a good fix please let me know.

Carousel72TRed

My inner heater/AC box I ended up bolting straight to the firewall pad, seems to compress into it nicely.

For the rectangular opening with the two vent flaps to the inside duct work I used (as suggested in this thread) some 1" self adhesive expanding foam weather strip from Home Depot. It was sticky enough to make it in one piece running it around the corners, then any areas on the protruding plastic lip that I could get to I used 3m spray adhesive ... it's staying in place very well. It will compress quite small with a gentle sustained pressure .. so when you go to install the underdash ducts you just have to press it in for a few moments to allow the foam to compress before screwing it down.

Way better quality foam than that cheap Styrofoam looking stuff in the Ames kit. I'm betting Home Depot has this stuff in a variety of sizes that I'm going to use to replace as many of the seals as I can instead of the crap in the kit.

AC/Heater Duct Inlet Gasket
 

Thank You Dataway. Looks like I'm going to Home Depot and get a roll of 1" expandable foam. I also have the wiring harness that hooks up to the positive post on the alternator that bypasses the resistor block so I can run the blower at full speed. I haven't hooked it up and tried it yet but it has a 30 amp fuse in line so hopefully it will work. Also all of my doors and actuators now work after spending many hours on my back tracing vacuum lines and my nose in my service manual figuring out what hooks up where. When I put the selector to bilevel one door is open and one is closed. Is this correct? I believe it is.

Carousel72TRed

When I was testing mine, yes that was the way it worked ... in fact I puzzled for quite some time with what the B/L marking meant ... then I realized with just one door open it probably meant BiLevel :)

This is the product I used for the big seal https://www.homedepot.com/p/Frost-Ki...EF41/310655227 Doesn't appear they make this same stuff in smaller sizes but with a sharp razor blade and some patience it could probably be cut down and used in other locations.

AC/Heater Duct Inlet Gasket
 

Thank you Dataway,
Did you put the weatherstrip in between the gap between the defroster plenum and the AC Heater Duct outlet or did you put it around them?

Carousel72TRed

I used that product to replace the gooey big seal that goes between the double flapper door and the duct work that bolts under the dash.

For the gap between the heater box and the defroster ducts I'm just going to get them as close as practical and put the screw in since it appears it's supposed to have a gap there.