As the temperature rises the engine will become more rich due to the lesser density of the atmosphere. Sitting that long, the carb could be gunked up some. This is not always the case but the fresh gas in the carb will soften the gunk and the engine will then run properly again. Take the cowl off and run on the ground for a short period. If it starts to run properly again you MIGHT be OK. If not the screen in the pumper side of the carb could be clogged or a fuel filter if you are using one. Take your time as this type of event is somewhat common. I am happy your plane is safe!
Another thought, is your engine baffled? If not it could have over heated some due to the higher temp but the increased idle says otherwise (I am saying overheating due to a lean condition). The proper setting of the idle screw will allow the engine to run slowly like your original idle speed of 850. The engine will speed up on the idle if it becomes leaner but it will be on the verge of quitting. This would indicate a fuel issue like I originally mentioned. -tom
Last edited by Maxam; 07-05-2016 at 07:15 AM.