Is it ok to work out all my arm muscles on the same day?

I work out my biceps, triceps, rear, middle and front deltoids, chest and abs for 4 hours for 4 days a week. I usually do it every other day. I've been doing this for like a year but I used to lift 5-6 days a week but stopped to let my muscles recover. I drink whey protein shakes after. I workout my triceps and some deltoids last so there getting all the protein. Should I separate my biceps, deltoids and triceps into different days or keep doing what I am doing.