Take him OUTSIDE to potty train him every chance you get and PRAISE everytime he goes outside.
3-4 hours isn't too long to crate but you should work up to that..little by little.. The longest I crate is 4 hours. Good luck.. Patience..
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Rhonda, Bailey, Josie and my angel Bella Rue'
"Until one has loved an animal, a part of one's soul remains unawakened."
~Anatole France~