I have been fighting an oil leak now for a while. I have replaced the valve cover gasket and it is not leaking now. I have replaced the hose from the head to the oil pressure sending unit with a steel line. I am still getting an oil leak from the back of the engine. There is an expansion plug(freeze plug) in the rear of the head and also one in the block just below the one in the head. Could either one of these possible leak oil? Does anyone on the site have a 230 out of the frame that can take a look at the rear of the engine and see if there is anyother place such as a pipe plug that could leak oil on the rear of the engine.