Used MMO, ATF &acetone, PB BLaster, Knocker loose, wd40 penetrant,, deep creep, all for a good long soak. Cyl 2 never leaked down, but the other 7 did. Thought the inside must be bad, but both top amd bottom end look great. Was going to take the rof cap off on #2 and see if crank roatated...