I've never had so much trouble with a thermostat housing...

I guess you will be taking that sucker apart again. Use the Indian Head sealer that will seal it for good, will be hard to get off next time but it will stick.

 

Same here, on more than one car as well.

 

Hi,

I had issues with my 65 300, I ended up finding a cast iron housing, made for a Jeep, and put a smear of gray silicone on both metal surfaces along with the gasket, let it sit for a day and also tighten it again after it warmed up, that was 2009 and haven't touched it since.

Regards,

 

I used that stuff to put my cork gaskets on my TA valve covers and they are still stuck on there 20+ been on and off a bunch of times too, good stuff.

 

Used indian head, seems to not like the heat. it got sizzly and bubbly. And goopy. I guess it seems to be holding, but it doesn't seem like the right stuff for the application, even though it says it resists antifreeze, even though the only place that is is in a cooling system.

 

I had this happen to me on my dual plane, and after chasing it for a couple weeks it ended up being the hose when I thought it was the t-stat housing. A second hose clamp solved the problem.

But since you've already confirmed it's the housing, I hope you find a good fix!

 

The Shellac seems to have done it. I also drilled a less than 1/8 hole in the thermostat. I wonder if it's not letting pressure build up once the car is off... or something? Takes a lil while longer to warm up as expected, but seems to be working fine. No leaks yet.

 

I always use a thin film of shellac on all my paper gaskets (both sides). I NEVER have any leaks either. I learned that trick years ago.

 

That 3M adhesive is the bomb.
I used it to cement two cork valve cover gaskets together to raise stock valve covers for roller rockers, and also to glue them to the v.c. for easy removal. And like Guy, they have been on/ off many times and still intact.

Don't get it on your skin.

 

I had a problem with this also. Turns out the radiator hose was pushed too far down on the thermostat housing. There is a small dimple about half way on the housing and when the house was pushed past this to the bottom of the housing it caused it to have a small leak. Pulled the hose back before that dimple and fixed the problem.