97 johnson 150 issue

I recently purchased a 189c blue wave with a 1997 150 johnson outboard. it had been sitting for 3 years but started right up and runs fine with no load. i took it to the lake for the first time today and had a few issues. The motor died a couple times but ran well at constant rpms, however i am not worried about these problems because i have not done anything to the motor other than basic maintenance and believe i probably have to clean the carburetors. The issue that i am woried about is that when i apply a small amount of throttle the rpms will increase slowly as the bow of the boat raises and the speed increases slightly, then when roughly 22 to 24 hundred rpms the motor will rev rapidly and the acceleration of the boat stops. It is almost like it is revving freely. On land when i shift into forward and spin the prop it turns the motor over, same in reverse. so i believe i have the shift rod set correctly. what could be the issue, it has a 3 blade aluminum prop that shows some abuse/wear but it doesn't seem to be bad enough to cause a problem. what are some ideas on what to check.

(so far i have drained the gas and oil and replaced with new, new water pump, and lower unit grease)

Re: 97 johnson 150 issue

Hello, been reading some other posings on this topic since I am having the same problem with my 1977 115 evinrude outboard. I checked the posting "1983 35hp Johnson slips and revs real high" and I believe the problem is the prop hub. Appears this occourrs when the rubber is worn or slips between the spindle and the prop. That is where I am staring.