I have a 60 evinrude and am stumped with what is happening. It idles just fine but as you put it in gear and slowly increase power to it the motor takes off on its on. It's like skipping from 2nd gear to 5th gear and i see no linkage movement when this takes place and can't find an air leak. Both carburetors were rebuilt a year or 2 ago and appear to be clean and clear and working appropriately. Has anyone ever seen this before? Any suggestions? It's bottoming out way before it is supposed to and also doing it on its own at times. Please help