My coolant has started mixing with the oil on my 03 kfx400. after taking EVERYTHING apart looking for the problem i found out that there are 2 "freezeout" style plugs inside the head. One of these plugs has apparently fallen out and been grinded to death by the cams. I've searched everywhere for a new plug and my local shop says "Kawasaki says to replace the cylinder head". Isn't that the purpose of the plugs? to save the head from cracking? I don't want to spend 3-400 bux on a new head b/c of a 25¢ part... So, does anyone know the exact size of these plugs? they look to be about 5/8" but i'm guessing they are metric? 14mm maybe? anyone have any ideas on where to get them??