1. Remove Coupler by tapping it clockwise (lose), then flipped blender over
2. Remove 4 screws holding base, once inside
3. Remove 4 more screws holding Lock-jar, 2 of those screws have spring with a washer,
remove broken Lock-jar.
4. installation of new parts is the reverse steps.
Note: At the end, Hand-screw Coupler Counter clock wise (Tight) last, install Assy-Jar properly, and Turn on blender to test.
Happy Blendings days.