Patent Publication Number: US-4729393-A

Title: Flushing adaptor and method of manufacture

Description:
BACKGROUND OF THE INVENTION 
     This invention relates generally to accessories for marine engines, and more particularly to adaptors or attachments for fresh water flushing of marine engines having lower housings such as those found in outboard and stern-drive engines. 
     It is well known that marine engines operating in contaminated and/or salt water conditions should be periodically flushed with fresh water to reduce contaminant and salt build-up within the water passages of the engine. In conjunction with boats which are regularly removed from the water then, having a means for introducing a supply of fresh water into the engine while it is operating otherwise out of water serves as an excellent preventive maintenance measure. 
     Until recently, all outboard engines included water intake ports which were positioned in the lower unit and the sides of the housing, in opposing fashion. These water intakes were so positioned at a mid-point in the depth or fore-and-aft dimension of the lower unit to reduce the possibility of foreign objects in the water such as plastic or paper sheet material becoming lodged around the lower unit and impeding water flow into these water intakes. These opposing water intakes lend themselves easily and conveniently to well-known flushing adaptors such as those disclosed in U.S. Pat. Nos. 2,661,631, 3,931,828, 4,108,190 and 4,359,063. All of these devices variously direct water into water intakes which are opposingly positioned in the mid-portion of the lower housing. 
     However, as small boats are being propelled faster with modern engines, particularly outboard and stern-drive engines of higher horsepower, as the speed of these boats approaches a certain critical speed, the shape of the lower unit, particularly the bulbous leading portion of the lower unit, has had to be redesigned to improve the high speed water penetrability of these housings through the water. It has been found that at these certain higher speeds, standard housing designs cause water separation from the lower housing surface, reducing or eliminating cooling water into these water intakes and also reducing available water flow to the propellers for propulsion. 
     In conjunction with these radically redesigned lower housings which include extended and sharply pointed forwardly portions for more efficiently travelling through water at high speed, the position of the water intake has therefore also required relocation. Typically, this repositioning of the water intake is to the lower forwardly surface of the bulbous now pointed portion of the lower housing. These water intakes are typically along or disposed symmetrically about the plane passing through the center of the housing and do not lend themselves to convenient fresh water flushing. None of the inventions described above are adaptable to provide a supply of fresh water into these so repositioned water intakes to accomplish this preventive maintenance flushing. 
     The present invention provides such a flushing adaptor which is adapted to be releasably installable around the forwardly portion of the revised, extended lower unit design and including fitting means positioned therewith so as to introduce a supply of fresh water into and in fluid communication with these newly positioned water intakes. A method for manufacturing these adaptors is also disclosed. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is directed to a releasably retainable fresh water flushing adaptor and method of manufacture thereof for outboard and stern-drive marine engines having an external lower propulsion housing which includes at least one fresh water intake port along the bottom forwardly extending bulbous portion of the lower housing. The flushing adaptor includes a molded cover which is mateably, releasably self-retaining over this forwardly portion of the lower housing and also includes a fitting connected or connectable into the bottom forwardly portion of the cover for releasable attachment to a supply of fresh water. The fitting has an internal passage in alignment and in fluid communication with the housing water intake. A water distribution groove formed into the interior surface of the cover adjacent the fitting for an increased water flow into the water intake is also provided. Releasable strap means either connected to or completely circumscribing lower housing and cover may also be provided to eliminate any tendency for the cover to be forced from disengagement with the lower housing by engine vibration or water pressure. 
     It is therefore an object of this invention to provide a flushing adaptor which is releasably installable onto the forwardly portion of the lower drive unit housing of high performance marine engines so as to provide fresh water flushing of the engine. 
     It is another object to provide the above invention which is particularly adaptable to modern lower housings which include water intakes at the bottom forwardly bulbous portion of the lower housing. 
     It is yet another object of this invention to provide a method of manufacturing the cover portion of the present invention which is precisely mateable onto the lower housing and water intakes to improve retention and eliminate water leakage. 
    
    
     In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with reference to the accompanying drawings in which: 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the invention. 
     FIG. 2 is a side elevation section view in the direction of arrows 2--2 in FIG. 1. 
     FIG. 3 is an inside view in the direction of arrows 3--3 in FIG. 2. 
     FIG. 4 is an end elevation section view in the direction of arrows 4--4 in FIG. 1. 
     FIG. 5 is a section view in the direction of arrows 5--5 in FIG. 3. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, the invention is shown generally at numeral 10 and includes a hollow molded cover or shell 12 and a fitting 14 which is connected thereto. The cover 12 is integrally molded of, preferably fiberglass material and includes a main portion 32 having an extended bulbous portion 18 blending into a narrower upper portion 16. Top opening 28 and back opening 30 are contiguous and sized to receive and fit around the lower housing L. Lines 26 and 40 represent the mating contour for the forwardly and bottom edges of lower housing L. Fitting 14 is connected to the cover 12 at the lower portion of the forwardly extending bulbous portion 18. This fitting 14 may either be permanently connected into the somewhat thickened portion 26 or may be threadably engagable into thickened portion 26 by threaded portion 20. The fitting 14 includes connector portion 22 which rotates in either direction A and includes raised knurled portion 24 which facilitates its connection onto the male end of a typical garden hose. The garden hose, of course, is connected to a supply of fresh water. 
     Fitting 14 includes thru-passage 34 which provides fluid communication between the water supply and the interior of the cover 12. This invention is particularly adapted to lower units which include water intakes W which are disposed in the lower housing L in approximately the same position on the lower housing L as is the opening of passageway 34 in the interior surface of cover 12. These water intakes W are generally disposed symetrically about the center plane of the lower housing L and may include one or more openings therewith. These water intakes W are typically elongated and longitudinally disposed. Although passageway 34 is typically sufficiently large to overlap at least one such water intake W, at least one water distribution groove 36 and preferably two, as shown in FIGS. 3, 4 and 5 are provided which both increase the area of fluid communication between passageway 34 and the water intakes W and also eliminate the possibility of reduced water flow into the water intakes W because the fitting 14 has been less than precisely aligned and positioned in cover 12. 
     These water distribution grooves 36 may either be ground into the interior surface of cover 12 or integrally formed therein as cover 12 is fabricated. 
     Method of Manufacture 
     The most accurate way to fabricate the cover 12 is by using an actual lower housing L as a mold. The lower housing L may be first coated with a releasing agent to prevent adhesion of the ingredients to be applied thereto. Next, the water intakes W must be blocked so that none of the ingredients will enter into and plug any of these intakes. This may be done by applying tape, or, alternately, a small adhesive mold which has the size and shape of the water distribution grooves 36 may be applied over these water intakes W for accurate placement of these water distribution grooves 36 in the cover 12. A combination of fiberglass mat and roving and polyester resin is then applied over the lower housing L in a well known manner at least covering the forwardly portion of the lower housing L in the shape of cover 12 as shown. After sufficient build-up of these ingredients has been applied, particularly adding build-up material at area 26 to receive fitting 14 and its threaded portion 20, the entire applique is allowed to cure and harden. 
     After curing has been effected, the molded cover 12, having excess material beyond that shown, is removed. The edges to openings 28 and 30 are then trimmed and smoothed to reduce burs and enhance appearance. 
     Fitting 14 is then either threadably engaged into a suitably threaded aperture in the cover 12 at 26 or may alternately be permanently bonded into a suitably prepared aperture in the cover 12. Placement of the fitting is important so as to properly align water passage 34 in relation to the water intakes W as previously described. If water distribution water grooves 36 have not been integrally molded, they must, likewise be ground into the cover 12 prior to installing fitting 14. 
     By molding the cover 12 directly over the lower housing L in this manner, the inner surface of cover 12 will virtually identically match and mate with the outer surface of the lower housing L. This has the two fold benefit of both providing increased releasable retainment of the cover on the lower housing L during operation and, secondly, to all but eliminate any water leakage from between the lower housing L and the inner surface of cover 12. Thus, virtually all water entering passage 34 and water distribution grooves 36 will be forced to enter into the water intakes W of the lower housing L for maximum engine cooling. 
     Although not shown in the drawings, where the mating fit between the inner surface of the cover 12 and the lower housing L is less than substantially perfect, a length of strap material may be used to wrap around both lower housing L and installed flushing adaptor 10 to reduce both leakage and to counter water thrust and engine vibration which would otherwise tend to disengage the cover 12 from the lower housing L. Releasable interconnection means such as Velcro or mating snaps will render the strap releasably securing for this purpose. Alternately, two separate lengths of master strip material may be connected at one end to opposing sides of the cover and wrapped in securing fashion around the lower housing L then releasably interconnected against one another by Velcro or the like. 
     While the instant invention has been shown and described herein in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of this invention, which is therefore not to be limited to the details disclosed herein, but is to be accorded the full scope of the claims so as to embrace any and all equivalent apparatus and articles.