After carrying out an oil change, the sump plug is leaking - could it be because I used a metal washer?

After carrying out an oil change, I have a leak from the sump plug. I used a metal washer from the filter pack, not a copper one, as I would have expected to seal the sump plug. Could this be the cause?
Given that the washer supplied was the correct one then we would assume that there are small cracks in and around the plug or that the plug is cross threaded. You may need to remove the plug again and check the area and threads, but also try using a cooper washer.
Answered by Alan Ross on

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