Hvac questions

So after waiting 2-3 years to have my engine rebuilt, the car finally made it on the road in october. The connecting rod bearings were to the copper so we averted a possibly problem down the road. It was a stock rebuilt and we just honed the block and used most of the parts that came out because they were in decent shape. We also slightly ported the heads to smooth out the airflow.

Anyway the other day the heat core cracked where thecone tube was soldered to the tank so now my whole dash is apart lol. I took out more than was necessary because there was a rats nest behind the clock and I wanted to make sure there wasn’t any others and so I could clean the pieces well. My heater box has 2 holes in it that before I had cardboard and duck tape covering lol. My question is inside the heater box there’s one flap that had foam insulation on it that’s now pretty bare. We drained the ac when we took the engine out so I only used the climate control for heat and it didn’t seem to blow out the defroster well. While I’m in there I’m going to look over all the plastic tubes running throughout to make sure there’s no leaks. I was wondering if you guys had any insight on what could be going on. Also my dashboard is in terrible condition and was wondering how much more is it to get that out? Is it just taking all the wires off by the steering wheel? Also this is the coolest car ever and I plan on fixing whatever it needs 😃. I’ll put pictures up later, I need to get them off my phone first

As hopefully youll be able to see since i had to resize the images off my phone, the dash is pretty cracked and i was thinking of having it redone while i have half of it already apart. The heater box has the flap from the top that is missing some foam, wondering if that makes a difference. Also i remember having the heater on and i thought that flap was against the right side of the heater box where the plastic grid is, if thats where it should end up or not Im not sure.

Whooo.

Your pictures made me wince and my palms sweat. That is SOME undertaking you’re getting into.

Given that our cars are 30 years (and more) older, you have to learn to be resourceful. IMHO, the first option should always be to try and replace bad parts. Looking at picture #6, with that huge hole in the heater housing, what I would try to do is replace the entire housing with another from a parts car or salvage yard (which will be pretty rare). You might want to contact 50RACER to see if he has anything. Replacing it also has the advantage of fixing any other “gremlins” (problems) that are haunting you, like the missing foam on the flap.

If that’s not an option—for whatever reason—then I would repair the hole with a piece of thin sheet metal and fiberglass matting. You can get sheet metal pretty cheap at places like Home Depot. (If you’ve never used fiberglass—it’s actually pretty nice to work with. I repaired a crack in my TC’s header panel with it last year.)

First, rough up the area around the crack with a Dremel tool or such, so the fiberglass will adhere better. Now, cut the sheet metal a little bigger than the hole, bend and shape it appropriately, and pop rivet it to the housing. (You could seal the repair with silicone gasket material, but fiberglass is more durable and it will take a LOT of silicone.) Work in sections. Cut a piece of matting (which is almost like cloth) a couple of inches bigger than you need and lay it over the seam of the sheet metal and housing. Then, using a paintbrush, spread the included resin over it, allow it to dry. Several successive layers of matting works best—you MUST apply them whilst the first layer is still tacky.

You need an airtight seal for the unit to work properly. Done right, it will be FAR stronger than it was originally.

As far as the cracked dash goes, you can get a dashcap overlay prepainted to match the OEM color for around $100 or so. Properly installed (it is pretty easy), everything will look like new.

The missing foam seals on the heater box can be replaced with closed cell foam from the hardware store and glued on with RTV, etc.

So after pulling the blower motor enclosure apart, i found there was a huge rats nest between the blower motor and the evaporator for the a/c. I'm pretty confident that was the reason it was not pushing the air through well. Also I fiberglassed the holes on the blower motor. All thats left is to re do some of the foam which i bought, and I ordered a dashcover from coverlay so just waiting on that.

Making great progress!!