I am sure the poster has called Delta, but in case anyone else wants to know: Make sure that while all parts are out of the valve to turn a bucket upside down over the faucet and turn the hot and cold water supplies back on for about 30 seconds. This will flush out any mineral debris that may be clogging the valve. It is imperative to use genuine Delta parts for the repair. The parts are patented and manufactured to very exact specifications and off brand parts will never work right. I work for Delta customer service and run into this every day.
[FONT="Times New Roman"][SIZE="5"]If you lack the courage to start, you have already finished.[/SIZE][/FONT]