Adjustable crankshaft fan belt pulley, 3-3/4" diameter, split

Precision machined aluminum. If your original pulley has been loose it may have worn the surface the of the crankshaft to the point where it is undersized. Putting a standard new pulley on may not fix this problem because it will still be loose. This split pulley will solve the problem. There is a allen headed set screw that tightens the pulley up on the worn crankshaft. It also has raised edges to keep the belt form slipping off.