A friend has asked me to replace the head gasket on a 740 tubo that got hot. Water got in the oil and I noticed upon disassembly that the turbo does not spin perfectly free. I just grabbed the impellor shaft after I took off the duct hose and twisted with my fingers, it feels smooth but somewhat stiff. The stiffness level is such that the turbine does not continue to spin after it is released. In other words it will not spin like a top. The driver says that he previously took off the induction hose out of curiosity (well before the overheating incident, during a tune up) and that the turbine did not spin freely for him at that time. The engine has 140K miles and although the body is just about perfect, I'm unsure if the car is worth fixing, especially if the turbo is bad. He brought it to me, his shadetree friend, after the dealer said $1200 minimum to replace the blown head gasket. I E there is not profit motive, for me, so I don't want him to spend more money than the car is worth.
thanks for any input.
8N