I used that "covering the intake' hack,until I bought a new engine. However, as was pointed out here, there are broken pieces inside the engine that may not play nice with other parts in there. There are many 31R Briggs engines out there that have failed for different reasons besides the compression release breaking. I don't know enough about the differences of the cams from 17hp 17.5hp and 18 and 19hp,so those cams may not interchange from one hp to another.