So last weekend I was out trolling and my engine died, it sounded like it was starving for fuel. After popping the cowling off I noticed I was missing a bolt in my 3rd carb..I guess its the intake vacuum port..I replaced it along with new brass gas fittings and a new fuel filter. It started up and ran for about 45 seconds then died again..now I can't get it to turn over. ..what has happened? Hurting to get in the water and fish!!