I have what I believe is a 1990 3 cyl Yamaha 40ELD Precision Blend Ser#6H4 L 419175. It has been stored on my boat in my driveway for at least 6 months. I noticed oil leaking from a drain hole on the upper half. When I tried starting it, it wouldn't crank. I removed the top spark plug which was fouled with oil, and then I tried cranking it. It spit out oil. I returned the spark plug and it started right up, but with quite a bit of smoke. I took a spin on the bay, but I didn't feel like it was running smooth. What's the problem? What should I do about it? New here, and need some help...