Recently I did E36 cooling system overhaul. After a few days, there are some leaking. I retighten the hose clam connecting to the expansion tank, but not sure if there is a washer in the engine block drain plug. If the parts # is really 07119919228 then it seems there is a washer 07119963201 from diagram then I must have lost it. If so, can I use new engine oil plug washer instead? It seems I will have to make a mess again.