The familiar "I ain't no plumber..." stuff is at least as old as 1916, because it was used in this:

http://www.worldcat.org/title/german-blues-its-neutral/oclc/24261434?referer=di&ht=edition

Lurtey was born in Kentucky in about 1887. _Billboard_ wrote on 10/28/1916 that "The German Blues: It's Neutral" was the "[b]est burlesque song on the boards" and on 5/26/1917 that it was "[m]aking a great hit everywhere."