The List
There are 120 4 letter words with Y as the first letter. The highest scoring is YUZU at 16 points in Scrabble. 1 of them contain no vowel at all: YMPT.
YAARYABAYACKYADSYAFFYAGIYAGSYAHSYAKSYALDYALEYAMSYANGYANKYAPPYAPSYARDYAREYARKYARNYARRYATEYAUDYAUPYAWLYAWNYAWPYAWSYAWYYAYSYBETYEADYEAHYEANYEARYEASYEBOYECHYEDEYEEDYEGGYELDYELKYELLYELMYELPYELTYENSYEPSYERDYERKYESKYESTYETIYETTYEUKYEVEYEWSYGOEYIDSYIKEYILLYINSYIPEYIPSYIRDYIRKYIRRYITEYLEMYLKEYMPEYMPTYOBSYOCKYODEYODHYODSYOGAYOGHYOGIYOKEYOKSYOLDYOLKYOMPYONDYONIYONTYOOFYOOPYOREYORKYORPYOUKYOURYOUSYOWEYOWLYOWSYOYOYUANYUCAYUCHYUCKYUFTYUGAYUGSYUKEYUKOYUKSYUKYYULEYUMPYUNXYUPSYURTYUTZYUZUYWIS