Hi. I recently bought. 78 mercury 1150. When I bought it, it started and shifted into gear well. However, there was little water coming out of the telltale, and it hadnt been run in a long time. So, I changed the impeller. When, I went to start it, the telltale was strong, but it won’t shift into reverse or forward. It revs up, but the propeller doesn’t spin. Any advice? Thanks.