Fouled Plugs
 

I know this is a Merc board, not a Volvo board, but am looking for advice everywhere.

I was having trouble starting my 85 740 turbo wagon w/ 162K on it so I decided it was time to change the plugs. Wow were they bad. starting at the front of the engine, the entire plug was covered with carbon, which decreased as I worked my way down the block. The fourth and final plug had little carbon, but had oil on the threading. Is this a sign my engine is on the way out? It had been about 20K miles since the plugs had been changed.

20,000 miles is nothing for plugs running on unleaded fuel, but I'm afraid there isn't enough info here for a professional mechanic to form an opinion. A professional mechanic needs to view a set of plugs to determine what is carbon, what is oil, etc. A very sharp image from a digital camera might work. There are myriad other questions that also need to be answered.

Sorry,
Peter

sounds like it's just running rich ,I never worry about a small amount of oil on the threads if there is no other sign of oil burning................

William Rogers............