Ive got a 1999 Suzuki dt 140. When I first put it in the water it runs great, but after a period of time it is like it loses power. Wont go above 2500 to 3000 rpms. No sensor lights come on, and the motor never quits running, it just wont pick up speed. 8 mph no matter how much you push the throttle. Any advice would be greatly appreciated.