[Elecraft] [XG2) Won't oscillate on 40m

[Chip Stratton]

Just got an XG2 of unknown provenance. Appears to have been carefully
assembled, and puts out a good signal on 80 and 20 meters, but 40 meters
output is nonexistent. The band-switch is fine, so I suspect either the
coupling capacitor before the crystal, or the crystal itself is bad.

Just for my edification, would crystal failure be an expected result if
someone transmits into the XG2? I'm trying to understand why only the one
band would go dead.

Thanks
Chip
AE5KA