Its holding. I had to drill the hole oval on the cable attchment tab to adjust it over about an eigth of an inch to get it to push the button in. Its working perfect. Just got back from a ride with the wife and no complaints about her feet burning.

 

Cool

 

My 77 Corvette is hotter than an oven also. I’ve done a lot of reading here and think I’ve got some directions.

About the collar over the transmission. I know the one that was in my 77 is missing. Not knowing any better, I took it out when I replaced the 350 with a 400. “What’s this old dried out foam doing here?” I thought.

I see Ecklers has the collar so I assume there’re widely available. But how do they go in? Can it be installed without pulling the engine or dropping the transmission?

I’ve got the assembly manual but I can’t seem to locate the collar.

 

Bibbyman
Yes, you can install the collar easily w/ engine/trans in, not that it makes a big difference.
77 had a valve to shut off coolant flow to heater core. The vac. tube to it is commonly damaged from under hood heat.

The blower runs full time in Low. I changed Low to Off.

 

You can also go to Home Depot and get a length of pipe insulation foam,anything to block the flow of hot air.

 

One thing I've not yet seen mentioned is the rubber seal that goes around the aft underside of the hood. This piece seals the back of the hood to its respective sill and prevents engine heat from spilling over into the vent well directly behind it. Since there is a pretty significant high-pressure area at the base of the windshield a lot of heat can get pushed through that vent well and into the cabin. Additionally, on AC cars there is a 'flapper door' inside the heater box which separates the AC/'cold' side of the box from the heater/'hot' side. This flapper door is surrounded by a felt seal that keeps the hot air from bleeding into the other side of the box and thus out of the cabin. Of course the entire box has to be removed and torn apart to get at the door and replace the seals. Even if you put a shutoff valve on the heater hose residual hot water still builds up in the opposite side (though it takes awhile) and radiates out of the heater core, so the only way to block it completely is to put a valve on BOTH hoses.
I've been chasing these issues on my '70 for years as well and have pretty much resigned myself to avoiding long drives in the summer. I've installed the tunnel collar, patched the tunnel heat barrier, replaced the heater valve, replaced the console control, put a new seal on the hood, etc.,etc. and have resigned myself to the fact that until I get the heater box properly rebuilt with new seals and the AC system properly flushed out and recharged (a previous "mechanic" goobered it up with R134) I'm just gonna have a hot car.
BTW, I feel your pain- I've made four trips to TX in the last two summers and have thought at least once during each trip "I could not have my C3 out here...just too freaking HOT!" Best of luck

 

birdsmith
I have made several trips to CA. w/ 77 A/C cool. So good, that I modified the stock system early so the Max. (high speed) had the lower speeds.


PS Someone did mention the hood seal so I didn't.