1994 Kenmore 90 series washer smells musty

I found that running about a quart of white vinegar through a cycle with hot water and no clothes or detergent takes care of the musty smell. Vinegar removes detergent build-up.

is the cold water all the way on?

if so, the first thing to do would be to check the screens in the cold water fill hose and the screen in the cold side of the water valve on the back of the machine. if that is not the problem then replace the water valve.

(turn the water off before taking the hose loose)

Towel mildew odor is transferred from the washer to towels and clothes. The washer must be cleaned first. After cleaning the washer and towels washing habits must change to stop mold smell from returning.

Washing machine mold / mildew is caused by:
#1 cause is overuse of detergents. Detergent companies are notorious for instructing to use too much detergent. Especially with soft water or when using liquid detergent no more than 1 tbsp of any detergent should be used.
#2 most common cause is using fabric softener because it's dispensed in the rinse cycle and will coat the inside of the outer tub with residue that is a food source for mold to grow.
#3 using only cold water for washing is fine but makes preventative maintenance very important. A weekly hot soak will dissolve odor-causing residue from inside your washer.
#4 not using the washer. If the clothes washer isn't used very often maintenance is especially important. If leaving for a vacation it's a good idea to clean your washer. Do a search to "remove washer odor" to read just how big the problem is. There are all natural washer cleaners that will also remove mildew odor from towels and clothing after the washer has been cleaned.

there could be buildup in the outer tub causing some water to stay trapped and causing the smell, try running some loads uning Ahfresh or you can try pouring lots of bleach in there and letting it sit a while, then run it throu a cycle.

This problem is caused because the water does not get totally pumped out of the outer tub and sits in the bottom of the tub and in the front seals. Eventually a mildew type scum develops and causes the washer to stink and also impart the odor to clothes. Even though front loaders do use less water and energy, all of them have essentially the same design and therefore all will eventually develop this problem.
Run a load with just bleach (about 1 cup) and white vinegar (about 1 1/2 cups) poured directly into the washer with hot water and it seemed to help, but this does need to be repeated about once a month or so...

but with your wife's Asthma tho you could try
Typically the cause is the machine itself, but occasionally the water being used in the washer can be the source of the problem. If the smell resembles rotten eggs, you may need a water filtration system installed. After you eliminate any other possibilities, you can begin the treatment process. Create a mixture of baking soda and vinegar. Add 1/2 cup of baking soda to 2 cups of white distilled vinegar. 3Begin a wash cycle using the machine’s hottest setting. As the water rises, add the baking soda and vinegar mixture. Let the washing machine complete a full cycle. If you notice any residue that has been loosened, use a cloth to wipe the surface clean. Run a cold water cycle to complete the process. You should immediately notice that the smell has been neutralized.

If you do not use a hot water cycle every so often it can contribute to the build up of mold or mildew inside the washer drain lines, pump and tub.. This is a common problem for those that only use cold water cycles. The detergent alone sometimes is not enough to kill bacteria. You also need the heat from hot water. I would recommend that you run a cleaning cycle on the hottest setting you have about once per week as a preventive measure. Add some bleach to the water to kill any existing bacteria. NOTE: This may take a couple of wash loads before you notice a difference. If you wish to conserve by not wasting water and energy by running an empty wash tub every week, switch to washing your whites in hot water with a little bleach to keep them brighter. This will kill bacteria in the washer in the process. I hope this helps you.

It sound like lint bult up under agitator orIn Between inner and outer tub it would have to be manualy cleaned thanks and good luck:)

The big door seal is probably the problem. Put on gloves and using a solution of Laundry detregent and hot water and rags, carefully wipe clean all the folds of the seal. It will be icky. Next run a cycle with some detergent and oxyclean or bleach if you have it.

Especially during warm weather, damp clothing left in a front loader mildew slightly very quickly- you can't really see much but you can smell it! So get the clothes in to the dryer immediately. You'll want to relaunder the smelly clothing after you have cleaned the washer.

Good luck to you and Thank You using FiX YA!

Aside from complete disassembly & cleaning it, try a hot wash on full with nothing in it except a bunch of bleach. 

What kind of smell is it?  If I can guess, I think it may be a musty or "locker-room" (sorry for bad memories) smell.  I have found that sometimes a change in detergent (or sometimes the same detergent you have been using for years) can cause build up and retain that musty smell.  I had to actually remove a inner basket completely and wash out both inner and outer drums to get rid of the funky smell.  She had used the same detergent for years.  Do you wash a lot of clothes in cold water?  This could also make the situation worse.  Try running a full empty load on hot with a bunch of bleach through the wash cycle, then stop the unit for a bit and let it soak and see if it clears up.  Also, try changing detergents and use a HE type soap.  HE causes very little sudding action, which in turn will stop the build up.  If this doesnt work, you may have to remove the inner tub and clean out both baskets (a lot of time, and need a special wrench, unless you know how to work it off).  Let me know if this helps any.   Jim