The shaft seal under my impeller on my Whirlpool dishwaster was leaking. I ordered an impeller replacement kit and have installed the seal, impeller, drain cover, spring and cutter, etc. I think I may have a pump alignment problem as there seems to be to much resistance in the motor. How much resistance should there be when spinning the impeller by hand? How critical is it to have the pump shaft lined up exactly in the base plate. Can you eyeball it or do you have to use a pump shaft alignment tool. I am pretty mechanical, but this ones got me beat. The motor trys to spin and then cuts out.

Thanks for any assistance. I guessed at some of the model number. I know it starts with DU and ends with Q12.