Im new to boating and have a dumb question about my drain plug so thanks for being patient. I have a 20 foot seville and a 1/2 inch drain plug ( so says my mechanic) the wierd part is I have a FULL set of sockets both metric and SAE but none fit !! I had to use an adjustable wrench to put the plug in. My MAIN question is the mechanic told me not to over tighten the plug so I first aligned it up and hand tightened it then used the wrench to finish the job. It seemed pretty tight but not ALL of the threads are in the hole, it only went in about 3/4 of the way and then it seemed awefully tight. Should it be in further ?? I took the boat out and the boat is stored in a slip and I have seen zero water in the bilge/engine area but Im afraid if I did this incorrectly the vibrations from the boat might loosen the plug and then I would become the proud owner of a sea ray sub :huh: