Re: 1956 Patrician heat riser

Posted by JWL On 2021/10/1 13:12:57

What you describe with the condition of one side of the exhaust is a classic case of a stuck heat riser valve. I don't know much this contributes to vapor locking, but a stuck valve will contribute to early failure of one side of the exhaust.

It is easy enough to check. If it is stuck try and free it up with penetrating oil or if this fails, replace. Many have hot been removed and the cars seem to work fine without them; albeit prone to carburetor icing in certain high humidity low temperature situations.