1991 300e blower motor problem (185K)
 

As I am set to have a valve job done on my '91, now I discover the blower motor is not working!! I did check the fuses and all seem ok. I know the A/C and heat work because I can feel it faintly coming out of the vents when I select with the temp wheel. Is this common? Any ideas for troubleshooting this issue?

You checked the fuse, meaning the large strip fuse, right? Over by the left strut support?
If the fuse is OK (or even if it's blown) probably worn brushes in the blower motor, I'd recommend a new blower motor. DIY job if you are a fairly experienced DIY'r

Gilly