Hi - I appear to have a very small leak where the pipe from where the oil delivery is pumped in to the tank - I put my finger on the threads of the large bolt and it had oil on it. I believe it only gets like that when oil is delivered and as soon as the level goes down a bit, it is not a problem as it is at the top of the tank. Is there a DIY option to "plug" of seal that whole area? Thanks in advance.