Oil pressure is normal. Oil level is normal. No leaks. Car ran normally. Sat for several hours. Started up and heard loud tapping noise at front of engine. Not sure if this is a water pump or noise associated with oil tubes breaking off.
Tapping noise at front of engine on 1992 Mercedes-Benz 500SL
It could be your Timing Chain has worn through a guide and is slapping around. This is not uncommon for a 500 Benz. If it is your Timing Chain, this is a pretty major repair expense.