I hear a clanking type noise where the viscious fan is.There is metal silver shavings on the left side of the block facing the engine.The viscious clutch fan moves in and out and up and down i suspect this is the problem.The pully should not move what has failed or loosened to make it move.It's awefully cold here and a trip to the shop without knowing is what is wrong is my priority.How does that centrifigual clutch pully tighten up.