The heat riser should close the damper when the engine is cold, routing the heat up toward the intake. As the engine heats up, the weight on the shaft should overcome the spring and route the exhaust gas straight down the exhaust pipe. If it opens on acceleration, the spring is wound correctly. If the valve is staying closed with the engine at normal operating temperature, the spring is too tight.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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