Passenger footwell leak 1984 el Camino.

[WordMan]

These cars were notorious for the seal around the evaporator/heater box leaking. I have found that windshield butyl tape (as sold by 3M and others) is the best sealant to use when replacing the original dum-dum like material. It stays flexible, and seals like crazy.

 

[Clone TIE Pilot]

There are also two holes on both sides of the firewall corners that are poorly sealed by the factory. To reach them you have to pull the entire front fender off.

 

[Rotech]

Is it a hole that I should be looking for under the AC box?

 

[Rotech]

These cars were notorious for the seal around the evaporator/heater box leaking. I have found that windshield butyl tape (as sold by 3M and others) is the best sealant to use when replacing the original dum-dum like material. It stays flexible, and seals like crazy.

is there a video or pictures in how to remove and seal the AC box?

 

[Rotech]

Let me explain how I discovered the leak, I bought a mint condition Malibu no rust on floors what so ever. Removed rug at my friend house. Left to my house and on my way it started to rain. Shortly after I looked at passenger side and saw a small drip of water. Do you think it can still be the AC box? The AC is not currently working.

 

[WordMan]

is there a video or pictures in how to remove and seal the AC box?

Don't know, but it should be in the Chilton manual, on how to replace the evaporator.

 

[Texas82GP]

is there a video or pictures in how to remove and seal the AC box?

A Google search will often yield the information you are looking for. I searched "g body ac box removal" and came up with these three links. It was literally 15 seconds of effort. The video is not the greatest but it will give you a good idea of what you are up against. Do your own search. There is more information out there. Not sure what year your Malibu is but consider buying the GM Service Manual. That will give you the true step-by-step. They are available out there used. I've included a link to the one for a 78.

https://gbodyforum.com/threads/how-do-i-remove-my-a-c-heater-box.31800/

http://classicoldsmobile.com/forums/general-discussion/49485-heater-box-removal-g-body-cutlass.html

https://www.diyrepairmanuals.com/proddetail.asp?prod=78ChvMalS&gclid=CPaV-qTWoM0CFVE0aQodG1kGgA

 

[Longroof79]

Guys, don't be afraid to do a search for a specific topic. Like Jared said, it takes little effort to find information. With leaks being so common on these cars, there's lots of info pertaining to the subject. Use your brain power. If there's something you don't understand, then ask.

I know butyl will seal the box forever, but I wouldn't suggest it. I've always used 3M Strip caulk. It also stays gummy and pliable and allows you to open, or remove the box down the road if need be.