I have a 1990 Mercury 150 on the back of my Astro 18FDX. I took it out for the first time this spring a couple weeks ago and noticed that it was pumping any water. I removed the lower unit and replaced the water pump. My problem is that I cant get the lower unit back in the motor. It appears that there is a bushing of some sort that has slipped and in the way of where the driveshaft slides into the motor. Is this a common problem and if so what is the fix?? I saw a youtube video where a seal came out with the drive shaft but this doesnt appear to be a seal. Any help would be greatly appreciated. I am at a loss and cant seem to find this part on any exploded views so I really have no idea what this is.
Motor Serial number is OC283818