Continue using hot water.

You can safely use chlorine bleach 5 minutes into the wash cycle. Wait at least 5 minutes to allow the enzymes in detergent time to do their job (bleach kills the enzymes).

When using chlorine bleach on color towels in your top loader, use the bleach dispenser or mix bleach with a quart of water and pour slowly into the wash (as washer agitates if possible).

On colored towels you can use 1/4 to 1/3 cup of bleach without ruining the color.
On white towels, 3/4 to 1 cup is OK.

I've use this practice on black clothing with no damage at all.

You could also try a prewash with your usual detergent & hot water followed by a regular wash with your usual detergent & add ~1 cup of white vinegar about 1/2 way through the regular wash cycle. Make sure you remove the towels promptly after the cycle ends and dry thoroughly. This has done the trick for me.

You could also try adding some Borax to the wash cycle + your regular detergent. Others have sworn by it, but it's hard to find in my area.

Hope this helps!

When I had a top loader, I used borax and it did the trick on our smelly towels.

Cj

Thanks, I think I will try the bleach and if that doesn't work ill get some borax. I was able to find some on amazon. What if I use color safe bleach?

Color safe bleach is not the same as chlorine bleach.

Chlorine bleach kills bacteria and mold which is making the towels smelly.