I agree with Meow - setting out a timetable with the hour that things occur might be the way to go to help in the meantime while you work on clock reading skills. You could even draw a clock with the time and then an associated picture/photo to go with it so he can match it up to a real clock ITMS.
I love this suggestion - b/c it is visual and then your DS can compare to a 'real' clock.

There is a clock that I got DD from a kids party plan type thing - I think it is a 'Doug & Melissa's' clock - you can move the hands etc... I'll check when I get home tonight (I'm at work tonight).