Sorry for the late response on my last post.
BTW, the best way to test a fan clutch is to get the eng to operating temp, disconnect the aux fan and throw something over the grille to stop air flow. Run eng to approx 110C (approx 2,000 rpm). At some point in time the clutch should lock up and start to roar (moving air), uncover the grille and the fan should pull air through the radiator until it has cooled down. The roaring noise should fade as this occurs.
92 Volvo 740 Wagon aka "Mutt mover"