I have a 53 MGTD that leaks oil whenever I slow down or stop. It comes out where there is a cotter pin towards the back of the bottom of the engine. It looks like a design problem. Is there any way to stop the leak?
Are you sure it’s the engine or is it the bell housing of the transmission? I haven’t looked at a TD in a while but a lot of older British sports cars had a vent hole at the bottom of the bell housing to let the oil which leaked from the rear crankshaft seal out. Without a place to drain, the bell housing would theoretically fill up and ruin the clutch. The cotter pin was supposed to vibrate around and keep the road dirt from blocking the hole. While it is possible that the leak could be coming from the main shaft of the transmission, it is more likely to be the rear seal on the engine. If it’s the engine, the oil is probably black. These seals weren’t the greatest when they were installed but I seem to remember seeing an improved version in the Moss Motors catalog a few years ago.