I noticed that the lower carb on my 1972 johnson 100 hp (100esl72) is leaking gas from two holes behind the choke valve. The engine is not tilted.; I notice this to happen minutes after starting. Is this a needle and seat valve problem or a vacuum problem. The upper carb does not exhibit this problem. If I throttle up it spits and sputters like to rich fuel mixture, but once full throttle and engine catches up, it runs fine. After throttling down and a few minutes have lapsed, the motor starts running rough again.<br />I pulled the leaky carb and found no buildup inside. The needle and seat look ok but am going to put in new carb kit along with new needle and seat. Any suggestions?<br /><br />Thanks for your help<br /><br />Chris