I'm not clear on what is happening now victa. Does the spring now stretch when you set the speed control higher than idle, and contract when you set it to idle? If so, progress seems to have been made, and the next issue is a broken governor. I seem to recall that the Quantum has the governor mechanism inside the crankcase, instead of having an air vane inside the cowl like previous B&S engines. Joe Carroll is the Quantum man, and can fill us in on that.
If you can post new pics with the speed control in min and max, and tell us something about what the governor link is doing, we can move on to that second fault. In most cases the governor link (the heavy wire connecting to the throttle butterfly) should move freely back and forth when the engine is not running, and when it is running, it should push the throttle toward closed, and push harder when the engine runs faster.
