I will give as much info as I can but the problem just started today.<br />I have a 1979 120 HP Mercruiser I/O. I replaced the prop, fuel line (with prime bulb) from 1/4 to 3/8 and fuel filter yesterday (flow direction is correct).<br />The engine started and went into gear fine afterwards. I put the boat in the water today and when I was at full speed I went to turn, then the engine died (I think I may have hit an underwater object due to marks on the new prop). It started up fine but then overheated and started making a bogging noise. I killed the engine and waited for it to cool. When the engine was cool, I started it back up and throttle would not move at allto put the boat into gear. We checked the cable, which was melted. We cut out the insulation at the bad spot, which freed it up. It idles with no problems and you can rev the engine manually at the carb, but when the throttle is pushed forward or back AT ALL to put into gear the engine stalls. <br />Further the fuel prime bulb goes flat when the engine revs but it stays running so it must be getting some gas. <br />I think it may be due to the underwater object but it could just be a coincidence. can anyone help.