Hello, Im new to the boating world and learning slowly by reading these forumns. They are incredibly helpfull. I have a couple questions regarding my 50hp Johnson. Its a 73 I think. Model no. is 50 ES73R. When i start the boat in the yard , its starts terrific. the first time i hit the key it will go, sometimes even without choking it. I have let it run in the yard with muffs on, then taken to the river which is across the road ( 20 sec away) dropped her in the water then have a hell of a time getting it going. Does anyone know what the problem could be? Also it came with 13 1/4 x 17 prop on a 14.5 ft chrysler tri-hull. Does this sound like a proper size prop for the engine and boat. The tach seems to reading over 6000 rpm,if its even working right. Any help would be appreciated.