After running my outboard 1/2 to 3/4 throttle for a while and then stopping to fish, it starts up OK but hesitates in taking the gas to get going again. After trying 3 or 4 times and feathering the throttle, it will run fine. I also note that the oil in the VRO did not go down (I also left the cap loose after filling)I have 50:1 mix in the gas as this is a new outboard to me and I'm not sure about the VRO. Before I go right out and replace the expensive fuel/oil pump is there anything else I should check out.