As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMELLED A BURNING, MUSTY ODOR DURING TAKE OFF AND CLIMBOUT. LASTED APPROX.. 3 MINS BEFORE DISSIPATING. PERFORMED FIM TASK 21-00-00-810-806 B737 NO ISSUES FOUND C/W ODI PREVENTION CH2172 DRAINED HYD FLUID FROM A SYSTEM TO 94% B SYS WAS 94%. (3737022)