1988 740 with B230F. Just changed the O rings on distributor to correct oil leak down back of engine. When I went to reset timing with a light the mark was at least 90 degrees out. Fortunately I made reference marks at distributor so my timing should be OK or close enough. It would seem therefore that the pulley/harmonic balancer rubber bonding has slipped. But I read in Steve Ringlee's FAQ that the non turbo has a solid pulley. Is this correct?

If I do have a slipped pulley what is the prognosis. Will it run OK for a while, can the pulleys fall off? Planning a 9hr trip Charlotte to Philadelphia. Should this be fixed immediatly.

You better change it. During your 9hr trip the fan can come flying off and damaging the radiator etc. You do not want to experience this. You have to change it anyway. Sooner may actually reduce your total cost compared to later.

As the slipping gets worse, things like the alternator and fan slow down, causing discharged battery and hot engine. Don't mess with a used one. They are all 5 years old and older. Get a new one.

The pulley has the harmonic balancer built in. It will still work ok, the worst thing that can happen is the pulley section will separate and cause lots of damage, the best that can happen is it will stay in place, but be a little squeeky. Your call, I recommend replacing it. How many miles on the timing belt etc. Then there are the seals, then the timing belt idler pulley, well the list goes on and I am famous for recommending the maximum for such things.

Good luck.

Believe all 230 engines have the harmonic balancer pulley. At least both turbo and na of mine do.

The balancer-pulley can come apart and cause a mess. You (IMHO) would be wise to replace it before attempting a long trip. Can find good ones in bone yards.

dick