Dominant new dog

Question
We have a 4 year old neutered hound which is very sweet and all was well until we recently decided to rescue an 18 month old  neutered rescue dog (I will refer him as the new dog) who is pestering this older hound. I always thought older dogs would teach younger dogs manners, but the hound is totally a push over. Only once in a while he may react when he has had enough, but very rarely. This new dog will do the following:
1) will obsessively pee on top of the hound's pee, is this a problem? should it be stopped?
2)will push the hound and bite him when we come home from work, the hound will howl in happiness and this seems to also increase the new dog's arousal levels, making him bite even more!
3) will push him away if there's food around and the hound will let him eat from under his nose
4)will pester and mount the hound when he's sleeping.

We are at our wit's end and don't know what to do to help poor hound. We have been seeing a trainer who told us to say "hey" every time the new dog is starting to pester the hound and reward him for stopping, and this initially really seemed to work, but of course, we can't be there 24/7 to prevent him and defend the hound especially since they spend time in the yard together, so he'll occasionally still be able to wake him up to mount him. I don't want to give this new dog away, any options? thank you for your time.

Answer
Barbara, it sounds like the younger dog would benefit from some basic obedience, self-control and manners training. You need to be able to call him to you, no matter how excited he is. If you're already working with a good trainer, this should be part of your lessons.

1) Over-peeing - Not a problem, and will likely continue.
2) If possible, keep them apart to greet them after you come home. This is something that could easily escalate into a fight.
3) Each dog should have his own separate eating area. Give them 10 minutes to eat and pick up any leftovers.
4) This is where your recall comes into play. Don't allow this behavior to continue. Give the younger dog something else to do with all that energy. Be sure he's getting enough physical exercise and mental stimulation so that he's tired out by the end of the day.

The older dog should have a safe zone to retreat to whenever he feels the need - it could be a crate, a room that you can gate off, or just spend time with you apart from the newcomer.

Let me know if you have further comments, questions or need clarification on anything I've suggested. Good luck!