I just purchased a 75 hp 4 stroke factory certified Merc and after I installed it, it fired right up, but won't idle. The lowest rpm the engine will run is around 2200. It has good throttle response in gear and I have double checked the linkage and the throttle is closed. I have contacted the dealer that I bought the engine from who is located on the east coast and they told me to take it to an authorized repair center because the engine is under warranty. The engine has a one year warranty from Mercury, but I am a little miffed that the factory could check out an engine and let it leave not running correctly. Not to mention that my closest warranty center is 100 miles away. I ran the engine for a total of 15 minutes with muffs on in the shop. If I turn the key off and restart, it will idle at around 700 rpms until I touch the throttle, then it immediately jumps to 2000-2200.