Join Date: May 2011
Location: Northern California
Try adding baking soda to your shampoo, lather him up, and let it sit for 10 minutes or so. Then rinse, and do a final rinse with a vinegar and water solution. Dry the dog as thoroughly as you can; put him in a crate with lots of dry towels and put a fan on him. Between baths, spray him down with the vinegar/water solution, especially on the trouble areas like under his chin and neck, ears, feet, or anyplace that stinks.
Labs tend to have an odor if they are wet all the time, especially black Labs. I don't know what it is about black dogs, but regardless of breed, they tend to have a distinctive odor. I call it "black dog whiff". The baking soda helps neutralize the odor, and the vinegar helps ward off growth of yeast, bacteria and mildew.
Alternatively, take him to a professional groomer!