My dogs don't get along with my new puppy...help!?

I have two chihuahua boys that get along great with all dogs, I mean ALL dogs. I've had the 3yr old since he was 8 weeks old, and since I have had him we have had a cat, and 3 other dogs stay with us- none he had an issue with. About a year ago, I adopted a new chihuahua, and since then, the two have been inseperable. Last night, I adopted a large breed dog, and my chi's are being SO mean to him. They bark and growl and even run up and bite his face. He's just a puppy, and wants to play, and I'm afraid if I let the "dogs do their thing" he will bite back and hurt them. Does anyone have suggestions? They have never EVER been aggressive to another dog, especially the older one, hes very submissive. I think that my younger, more fiesty, chihuahua is influencing him. Whatever the reason, it needs to stop! I would be heartbroken if I had to give up my new puppy, but also, I want to be able to bring new dogs into my house and this behavior is unacceptable. If they don't accept this pup, who will they?