Valve Train Analysis - Valve Spring Retainer and Valve Spring Retainer Keys, Valve Tappets Removed

WARNING: This page is about a different car, the 2009 Mercury Sable, 2009 Ford Taurus X, and 2009 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.

Check for correct seating of the valve spring retainer key on the valve stem and in valve spring retainer.
Check for correct seating on the valve stem.