Heating intake manifold

[jjohn]

When I started the motor I notice there is lot of heat in the carburetor intake part, see image red circle.
Is that normal?
I was think if the gasket between the metal and exhaust should work like an isolator to minimize the heat?
Or maybe some other problems ?

[Articifer Tom]

My understanding is that is purpose of that bulge , using exhaust gas to heat and vaporize the intake .

[Russ T. Fender]

I believe that is also why so many of them are cracked.

[jjohn]

Ok thanks
I can see a very thin crack maybe a half inch going to one of the vacuum port. Maybe drill a small hole to stop and use JB-Weld to repair?

[Russ T. Fender]

That might work but the crack might have to be opened up for the JB Weld to adhere.  I have used it for that purpose with good results.  That said I have been running an intake manifold that appears to have a crack for years without any issues so you might want to leave well enough alone if the car is running well.  The crack has not grown any over the years.

[jjohn]

Thanks for good info