Washer

When overhauling the engine, replacing as many of the wear items as possible in the oil pump will simplify the reassembly and in this case, ensure the correct supply of cooling, lubricating life blood (otherwise known as oil!).
Other oil-pump related parts you may wish to consider:

161420063
161420746
161421146
161600152
920431263
920551571
920553018
921511234
132BC0660

Order all the gaskets, seals and new fasteners you will require at the same time and reduce the shipping costs with one larger order.

Pro-workshop gasket sealant 08C70K0234M to complete the job like a professional.

This part may have other applications in the Kawasaki model range - ensure the part-number is correct for your model?