Heat Riser.

[CRUZE 418]

OK guys, just rebuilt my '72 318. The passenger side exhaust manifold heat riser was trashed. Bought an NOS repair kit, thought that I understood from the directions how to install the stop bar and spring. The spring when heated seems to go in the wrong direction . I have tried all 4 positions that the spri g can be placed, all to no avail. Read a post on a /6 post and disagree with, The spring expands and the blade is open when cold, shut when hot. This makes absolutely no sense to me. The spring contracts when heated, and pulls away from the pin that is the shaft stop. Will try and send a picture. Well, as usual, photos will not load. I hate this, new S21 phone and a photo goes to 100% and then the error pops up, tried different lighting and same result. Damn

 

[Murray]

How it works- the purpose of the thermostatic spring is to provide more tension on the butterfly when it is cold. When the spring heats up it relaxes that tension allowing the butterfly to open easily thus sending fewer exhaust gasses to the intake manifold. When warmed up the butterfly still has a tendency to close, but now easily opens with exhaust pressure. It never completely opens unless it is sticking.

 

[CRUZE 418]

I have the idea of how it's supposed to work, I just cannot get it to work that way.
I am missing something, I have tried how I think it should work, and I have the installation instructions. I don't think that I am going to solve this on my phone. I will have to find a hands on person!
Thank you!