Hi, I have a '79 Evinrude 85 HP that I bought recently, and I took it out on the lake for a bit. By the end of the ride, it was ideling very fast in nuetral, and would not calm down unless I put it in gear. The guy I bought it from said his son was messing around with it back by the throttle cable. How do I adjust the timing? What could be wrong with this thing, and how can I fix it???? Thanks for any advice!