Chunkerz

While I have my dash out I plan to rebuild the HVAC box because all of the foam seals are rotten and letting air past. I cannot find any write ups on removing it, so does anyone have any tips for removing this thing? I have all of the fasteners that I can find removed, but it won't budge. My car has A/C, so does that add any extra steps that I should be aware of?

V2Rocket

Early car its a breeze, late car way more difficult.

Butters944

My early car was a pain in the ****, can't imagine how the late cars are then. Good luck Jeff...

Chunkerz

Removing the fan allows me to wiggle the box quite a bit, but the heater core and A/C lines appear to be the last things holding it in. I am hoping that I can pull the box forward and to the left and slide the heater core out so I don't have to drain my fresh coolant. How do I disconnect the A/C lines? I assume the system needs to be evacuated first?

plumbum

I have never done it on a 944 but if you are looking to pull the whole box you will need to remove or at least unbolt the Evaporator and heater core. The ac system will need to be evacuated first..cap off the system to prevent moisture from getting in.

MAGK944

They built the AC box then built the car around it

Seriously it's a huge pain on late cars so if you find a good way to do it please do a write-up. iirc the AC hard lines are bolted to the firewall and the expansion valve needs to be removed first if that helps.

Chunkerz

How do I unbolt the evaporator? There is black foamy tar stuff covering what I think are the connections at the evaporator.

Edit- I got one of the hoses to the evaporator off. All that came out as a slight hiss for 2 seconds, so I guess that explains why my A/C didn't work. The other hose on the evaporator appears to be one piece and runs through the firewall, so I guess I have to drain all of my fresh coolant and remove the plate that the A/C and coolant hoses run through It looks like the bolts are only accessible through the engine bay and are right behind the cam tower, so they're going to be a bitch to remove.... I don't see how to disconnect the A/C line in the engine bay. It looks like it's all one piece.

Whoever designed this HVAC system needs to be shot...

Chunkerz

16 months later and it's finally out....

Any recommendations for the type of foam to use on the flaps? Should I look for something special, or will any old foam from Home Depot/Lows work? I never ever want to do this again so I want to get it right the first time.

Grandpa#3

I used regular door/window sealing foam from lowe's. So far it has worked real good now for over a year, for some door flaps I used thick felt with contact cement. It should outlast my ownership.

Cheers,
Larry

Chunkerz

Did you use contact cement on the foam too, or just the felt? What did you use for the gasket on the top of the box where the blower motor sits? More foam?

Chunkerz

Alright, so I went to Lowe's and 2 different Home Depots and this tube foam stuff is the best I could come up with. My plan is to cut a slit down the side, fill it with contact cement, then slide it over the edges of the flaps. Think that'll work?

Here's what I got....

Chunkerz

No thoughts?

Tiger03447

BTW, Chunkerz..just thought I'd let you know..that when you go to hook your AC system back up, you'll need to replace the receiver/dryer unit..Once they see air for more than 20 minutes, they're toast..just an aside...Good luck with the HVAC system...Thanks,

Chunkerz

Yeah, I know. Expansion valve, drier, compressor oil, etc is all gonna be replaced if I decide to keep my AC.


No thoughts on that foam? I really really really don't want to take this thing out again....

Chunkerz

Still no thoughts on the foam? I'd like to get at least one opinion...