Well.....I hope this helps with the oil smell, I am sure others might have better suggestions. My son races various toys hehe, snowmobiles, dirt bikes, 4 wheelers....just about anything with speed hehe. I wash his gear and towels and such with Oxi Clean and they come out brand new and there is never any left over oil smell. If you dont have that....maybe a cup or two of bleach and fill washer with warm or hot water
let it sit and soak for a bit and then let it rinse out.
Good luck...hope it helps.