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Discussion Starter · #1 ·
Pulled the heater/blower tonight to replace and upgrade the extra crispy resistors. Before I started I was surprised at how poorly the AC worked. Now I'm surprised any air at all made it to the cabin... Just leaks and poor sealing EVERYWHERE. I'm following Michael's recommendations for AC upgrades but wondering if anybody else had issues with the foam around the blower itself? Mine is separated in a few spots and pretty much crushed and deformed in most others. I need to glue the first layer of foam back down, but I'm thinking I need to replace the second layer so it forms a new seal. Otherwise if I don't get it back exactly right it will probably leak even worse.

Did anyone upgrade/replace the foam for a better seal before they replaced the assembly? What did you use?

Mav
 

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Hmmm. May have to look into this myself. The crush patterns sure look like the thing was improperly installed.
 

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mine was in much better shape but I still used some contact cement to reseal in some areas.

I think you can do some "home depot" engineering to fix or replace yours
 

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I did this a few months ago. I used a square adhesive backed closed cell foam about one inch square from a local rubber/foam supplier. I removed my old foam that looked much like yours. Works well now.
 

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Discussion Starter · #6 ·
I did this a few months ago. I used a square adhesive backed closed cell foam about one inch square from a local rubber/foam supplier. I removed my old foam that looked much like yours. Works well now.
I'm guessing you just replaced the top layer also with that? I like that suggestion but hoping to pick up everything from Home Depot, so I'm going to look at some weatherstrip foam today which Im pretty sure is also closed cell.

Thanks all for the feedback! Will follow up with pics. No..really, I will.
 

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Discussion Starter · #7 ·
Foam Upgrade

As promised I have returned with parts list and pics. I'm going to detail the whole thing since it was more difficult than I expected to get everything right and took a couple of days of trial and error.

I was able to get everything at home depot. It all fit up nicely when installed back in the car. I have a few tips on installation as well. Trying different things I've pulled out the blower and ac unit now more times than I care to admit, so I'm a de facto expert at this point.

Tip 1 replace blower foam "gaskets". I more or less mirrored the stock design with what I feel is superior products and mounting so hopefully they won't deteriorate, separate, or rip off upon installation. I tried a few things but what ended up best was:

1 package of closed cell foam air conditioning tape:
43374023114 FOAM TAPE <A> 3.49
MD 1/2"X3/4"X10' FOAM WS-3 YR

and 1 package (I bought 2 just in case but 1 is enough) of 1 1/4" foam air conditioning weatherstrip. This is very soft, compliant foam for the outer seal but should hold up better than the factory stuff which basically disintegrated when I removed it.
043374020069 A/C W/S <A>
MD 1-1/4"X1-1/4"X42" AC WS-GRY
[email protected] 3.98

First I removed all the old crap and cleaned up the housing really good with 3m adhesive remover and various dremel tips.. ss brush etc. Then final clean of the surface with rubbing alcohol.

I also utilized weldwood contact cement, also avail at HD to get a really strong bond on the different layers. I love this stuff, it's sets up really quick so you can get the gaskets exactly where you want them and it seems very strong.

I used 2 layers of the 1/2" ccf tape on the firewall side layered on top of each other and one layer on the opposite outside air intake side. I measured the clearances on my car and this was perfect after the 1 1/4" foam was added. Too thick and they will tend to pull/tear on installation, too thin and the seal will leak.

After the 1/2 ccf tape, I contact cemented the 1 1/4" foam on top of that and glued the ends together to make it a ring. Can be seen in the pictures.

For installation here's what works great to make it quick, easy, and not do any damage to the foam on installation. I used 2 sheets of thin aluminum sheeting on either side to make a channel for the blower to slide down. (see pics) I wet both sides and the foam on the exterior with a water/soap solution to make it slippery.
This worked like a charm!! It slid easily down to the bottom and compressed automatically as it slid down the channel which narrows naturally as it goes down. Then just a little nudge at the bottom towards the blower openings and it popped right into place and the gaskets were in perfect shape and they sealed up really nice against the walls.

Getting the AC assembly installed and mated up was exceptionally challenging due to the positioning but a long screwdriver used to pry the two lips apart worked really well and they finally slipped perfectly into place.
 

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Discussion Starter · #8 ·
More pics

Here's just a few more pics of the materials and what not.

One more tip I forgot. I tied a string to a piece of convoluted tube and taped it then threaded it through the channel. Then I tied the string to the drain pipe so I could remove it from the car and attach it to the ac unit. Then I just pulled it through the channel using the string while threading the AC unit back into place. Then I knew for sure the tube wasn't kinked up underneath or anything and it made installation a lot easier in my opinion.
 

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New shiny wizard radiator and replaced the resistor pack. Recharged AC and now it is time to end this headache.

Heat and AC work MUCH better.

Auto part Engine Motor vehicle Vehicle Car

Land vehicle Vehicle Car Alloy wheel Automotive design
 

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The openings at each end of the blower and sealed with foam, are only the air into the system, not cold air going out. My point is that a leak there is unlikely to affect the cold air into the car too much. Yes it can affect recirculation, but probably not much else.
Michael
 

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Discussion Starter · #12 ·
The openings at each end of the blower and sealed with foam, are only the air into the system, not cold air going out. My point is that a leak there is unlikely to affect the cold air into the car too much. Yes it can affect recirculation, but probably not much else.
Michael
Well it works for recirculation and on the same principle as sealing up the front intakes, the more warm air the system pulls from leaks instead of from inside the car the harder it has to work to cool the cabin and the less cold air going out. Our system being what it is and as inefficient as it is, every incremental gain can be a win. But I don't need to explain that to you, you wrote the book on half of this stuff so I'm little surprised to hear your stance on that.
 

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Well it works for recirculation and on the same principle as sealing up the front intakes, the more warm air the system pulls from leaks instead of from inside the car the harder it has to work to cool the cabin and the less cold air going out. Our system being what it is and as inefficient as it is, every incremental gain can be a win. But I don't need to explain that to you, you wrote the book on half of this stuff so I'm little surprised to hear your stance on that.
I am not disagreeing with you, just stating the a leak on the input side is not as important as on the cold output side. Certainly the AC would be less efficient with an input leak, but it "may" not be detectable to the "seat of the pants".
Stay cool.
Michael
 

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Discussion Starter · #14 ·
I am not disagreeing with you, just stating the a leak on the input side is not as important as on the cold output side. Certainly the AC would be less efficient with an input leak, but it "may" not be detectable to the "seat of the pants".
Stay cool.
Michael
Well I am a bit superstitious after 7 years of sweltering even with my AC on high so I just went after ounce I could get. I went so far as to pull out the recirc plenum and insulate the inside (see pics) plus everything else in your AC mods and Tony Wa's.

The recirc plenum actually just pops out in two pieces once you have the blower and HVAC out so it's actually pretty easy. Interestingly it's just a thin plastic duct right on the other side of the recirc foot vents inside the cabin so insulating it for sound if for no other reason seems like a good idea if you open your footwell vents. But I'm sure it does help insulate the cabin and the recirc air a tiny bit.
 

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I would do the same if I had access, good work.
Interestingly enought, I think there is appreciable leakage in the HVAC box, enclosing the evaporator.
Michael
 

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Discussion Starter · #16 ·
I would do the same if I had access, good work.
Interestingly enought, I think there is appreciable leakage in the HVAC box, enclosing the evaporator.
Michael
What are your suspicions there? I patched up around all the in and out plumbing , there were pretty massive openings around all that. Are you referring to the housing itself?
 
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