Bruce K Wolford

US Patent:

7004802, Feb 28, 2006

Filed:

Aug 31, 2004

Appl. No.:

10/931342

Inventors:

Bruce D. Wolford - Spokane WA, US

International Classification:

B63H 11/103

US Classification:

440 47, 440 38

Abstract:

A tail cone assembly for a watercraft jet pump includes a tail cone body with a shuttle recess, a self-actuated shuttle biased into the shuttle recess, and a pump back pressure inlet orifice through the tail cone body and into the shuttle recess. The shuttle may have a rear portion with an outer conical surface of at least two different conical slopes that are positioned to determine two discrete stages of jet pump discharge area. The shuttle recess may include a side wall with a grit exhaust groove therein. The grit groove and inlet orifice may both be positioned at gravitational low points within the assembly. The assembly may further include a grit screening device associated with the inlet orifice that restricts grit having a size greater than or equal to a shuttle clearance from entering the inlet orifice.