To allow a valve guide to be easily housed in a valve case by using synthetic plastic to make the valve guide, fitting a C-ring to the valve guide on its outer periphery, using a casting for the valve case, and providing a groove in the inner periphery in which the C-ring fits.

A jet pump 100 uses a vacuum generated from high-speed spurts of water to draw water in through a strainer 116 and sends it via a throat tube 112. A valve case 10 is one-piece molded with synthetic plastic, in which a valve 12 is housed. To guide the valve 12 in the vertical direction, a valve guide 14 is secured to the upper portion inside the valve case 10. This valve guide 14 is made of synthetic plastic and a stainless-steel C-ring 20 is fitted to a pair of support portions 18, 18 provided in a protruding condition on the outer periphery of the valve guide. A groove 22 is formed on the inner periphery of the valve case 10. The C-ring 20 is engaged with the groove to secure the valve guide 14 inside the valve case 10.