If you can, let the parts sit overnight. But if you can't, like me, just give them 15 min. Now get out the WD-40. Get one HLA and put the Jewler's screwdriver in the bottom. When you push a valve should move. Now squirt some WD-40 in there and then clean the rest of the HLA with it. Once you're done, try and squeeze the HLA with your hand as hard as you can. If the HLA squeezes, it's bad. Get one HLA from the 12 you took from the yard and throw it in with the rest of them in the bucket. Once an HLA passes, put it aside.