<<<Not sure it would fix one that already smells>>>
On an LG washer---if a musty odor is present---using Tide Washing Machine Cleaner is very effective.
Disinfectant (kills bacteria that causes odor)
Scum Remover (bacteria grows/colonizes on scum)
In some instances---a customer's washer may be so "contaminated"---that multiple Tub Clean cycles are needed to remove the bacteria/scum.
On older non-Tub Clean models the following helps:
1) Add Tide Washing Machine Cleaner into washer tub (no laundry)
2) Close door.
3) Press & hold the SOIL LEVEL and SPIN SPEED buttons
4) Press the POWER button and release all 3 buttons (wait for door to lock/single click sound)
5) Press the START/PAUSE button 6 times at one second intervals (hot water fill)
6) After the hot water stops filling---place the washer in tumble test mode.
This test mode varies on different models---but is usually the 7th---8th or 9th step in the test mode (pressing START/PAUSE button)
7) Leave washer in *tumble mode* for three hours
Turn off washer
9) Turn on washer and select the SPEED WASH cycle and press START (to be used as a rinse cycle)