I have a mercury 8hp 1989 I believe. It runs great no problems until yesterday. While heading upriver all of a sudden the boat slowed and the rpm's went up. I thought I had grass on the prop, but there wasn't. At low speeds its fine at higher speeds the power cuts and the rpm goes up. At one point it made a slight clunk sound. I removed the gear case oil and it looks normal. I removed the lower end to see the drive shaft and there is no problems with that. Could there me some internal issue with the engine causing this? I don't understand why the rpm's raise but power is cut. The engine temp is cool to the touch also. Any help is appreciated.
