I was replacing the impeller on my outboard when I noticed that the little pin in the shaft that engages the water pump seems too low. It is only about 1/8" above the lower plate. I was going to drop a single bearing down the hole to raise the shaft height a little when my better judgement told me to find out whether the pin height is indeed an issue or if it is what would be the proper fix. BTW - I was replacing the impeller because I bought the outboard used and it looked like no maintenance had ever been done. It was sending out a stream of water under operation before I decided to perform this "regular" maintenance. Any ideas?