I have a 1986 120hp johnson that I had rebuilt several years ago. I ran one tank of gas B4 i was injured. I got it out recently and found that the lower unit had water and no oil in it. I drained it and filled with oil. Ran it in the lake for about 30 min. and drained the oil again. It had no water and some very light shavings. When you spin the shaft it makes lite noise. Question is do I need to replace the bearings, if so how do i remove the lower unit. Any help here will be greatly appreciated.