Join Date: Nov 2000
Thanked 0 Times in 0 Posts
I apologize for mentioning the power valve when there is no reason to focus on it. It produces enrichment of the mixture when vacuum is low, which typically corresponds to having the pedal down significantly. It can get stuck on old dried up dirty carbs, and it can get ruptured. It has a rubber diaphragm that gets sucked down and closes a valve. If the diaphragm is ruptured, the valve stays open and excessive fuel pours out into the venturi's. You can test it by removing it and putting to a vacuum source, which in my case is my lips. I shouldn't recommend this for others. Probably some nasty poisons in gas and its sediments. The diaphragm must be intact, and the valve must move freely against the tension of an internal spring.
Look first for vacuum leaks, and correct idle mixture settings.