ICQ>

> I just changed my spark plugs on my 1989 740 GLE (16V)and

> found that the old #1 & #4 plugs were covered with fresh oil.

I kinda hate to admit that this is familiar territory on my '89 16-valver.

1) Oil collecting at the bottom of the plug recesses on a B234F engine can easily be a leak between the valve cover and the head. You might want to try just cleaning it up and re-torquing the valve cover nuts (try 12 ftlbs). If this was left unattended for a long time then the spark plugs or ignition wires may be oil vapour contaminated leading to arcing and misfires. If the problem recurs then new valve cover gasketing is in order at which point the cam seals and timing belt should also be inspected for escaping oil.

The back pressure from a plugged flame trap will make such oil leaks all the worse. With the engine running, loosen the oil filler cap and do the old suck down test. If it rattles loosely or there's no apparent suction holding it down to the cover then clean/replace the infamous flame trap element. Make this part of your routine B234F service along with inspecting and cleaning the intake throttle body and hose connections.

2) Wet carbon fouled spark plug tips and threads (which may look oily) might be a sign of plug blowby. I had this happen on my '89 B234F with a cold engine and plugs that had worked loose. The engine will tend to run rich, have a rough cold idle and be sluggish. I've needed 22-24 ftlbs (more like the cast iron head spec) rather than the 18 ftlbs (aluminum head dry thread spec) to keep my plugs seated. Just don't overdo it with aluminum heads, especially if you're using a thread compound.