My '76 240D w115 oil pump seems to be losing its prime after sitting for long periods of time. On initial startup it takes a full 10 seconds to peg the oil gauge. I'm sure it is not the gauge, because the engine is definitely smoother and quieter once it reads full pressure. Once on the road, it behaves quite well, holds appropriate pressure, and doesn't smoke any more than expected. It only sees about 200 miles per year, but I'm afraid to start it up too many more times before I attempt a fix. I know the pump is still available, but I recall seeing somewhere deep in the forums that someone here rebuilt their pump, complete with instructions and part numbers. That thread has proven to be elusive, despite numerous searches. Can anyone help with this? Has anyone here rebuilt their own oil pumps? It should be noted that this is a relatively new issue. Before last year, the gauge took just a couple of seconds to rise to the top. Now it is much longer.