1. Field of the Invention
This invention relates to a novel, yet simple system and process for flushing inboard/outboard marine engines and inboard marine engines with a desired fluid. This system and process allows for any person to quickly and easily flush an engine whether the boat is in the water or out of the water with the engine running.
The need for such systems is commonly seen with marine engines. When a marine engine is operated, in fresh water or salt water, impurities in the water can cause cooling problems and corrosion of components if not properly flushed. Debris of various types can be picked up in lakes and rivers, and even the cleanest ocean water is going to have salt in it. Therefore, it is imperative that marine engines get flushed after every use.
The difficulty is that flushing marine engines, especially some inboard/outboard engines, can be very cumbersome since the intake for cooling fluids is in the vicinity of the propeller. The intake for inboard engines is usually under the boat, with the intake pump located in the vicinity of the engine. In either case, the intake points for flushing the engine are difficult to reach, and the intakes remain underwater unless the boat is physically removed from the water.
The invention eliminates the difficulty of the flushing process. This system has no valves to clog or components to corrode, is accessed from the topside of the boat, is simple to use, is inexpensive, and is easily installed by one that is not versed in the art. The novelty of this invention is in its simplicity.
2. Prior Art
There are a number of approaches to flushing marine engines. Some are designed to flush outboard engines, some inboard engines, some inboard/outboard engines, and some a combination of engines. Those that are known that will work for inboard and/or inboard/outboard engines, such as the present invention, are: U.S. Pat. No. 3,550,612 issued Dec. 29, 1970 to Maxon discloses a purge valve for cooling fluid conduit system; U.S. Pat. No. 4,619,618 issued Oct. 28, 1986 to Patti discloses a fresh water flushing kit; U.S. Pat. No. 5,251,670 issued Oct. 12, 1993 to Bates discloses a flush valve; and U.S. Pat. No. 5,295,880 issued Mar. 22, 1994 to Parker discloses a flushing valve for inboard boat engines, and U.S. Pat. No. 5,830,023 issued Nov. 3, 1998 to Brogden discloses a mini freshwater flushing device.
For the most part, the devices prior to this one involve elongated conduits with multiple valves, manually operated valves, check valves, or have complicated directional control valve mechanisms. Such devices inherently require proper performance of sequential steps that must be completed and then reversed at the end of the flushing process, or rely on check valves, directional control valves, or other devices that are supposed to perform in a specific manner while flushing the engine and then perform in another manner when not in an engine flushing process.
The combination of complicated operational procedures, fluid flow design and flow design components, and the physical locations of such prior art devices often presents the risk that an improper operational procedure or an unknown malfunction of a fluid flow component will expose the vessel to taking on seawater, not functioning correctly under normal operation which can result in ruining a marine engine and/or outdrive components, or at the very least, not properly completing the task for which they are designed, that is, thoroughly flushing a marine engine.
In Maxon and in Parker, a device is situated in the coolant flow path and proper operation of the system is dependent upon either a ball or similar component being displaced by the incoming cooling fluid. Then these components are displaced in the opposite direction during the flushing cycle. While these devices avoid the need for manual intervention, the constant exposure to corrosive environments, abrasive contaminants such as sand and mud, and larger floating debris, can lead to component failure, valve seat failure, as well as failure due to large debris being trapped within the device. This all leads to an inherently unreliable fluid control system over the life of the vessel.
The other significant limitation to both of these devices is that they cannot be used with an inboard/outboard marine engine that has the coolant pump in the outdrive. Any device that is to be used on an inboard/outboard marine engine that has a pump in the outdrive must contain a method for dealing with the fluid that is being pumped from the outdrive. If fluid from the outdrive is not allowed to continue to flow, the pressure on the outlet of the outdrive pump will increase and the pump will, in a matter of just a few minutes, fail.
In Patti and in Bates, a device is also situated in the coolant flow path, and these devices are designed to work with both inboard and inboard/outboard marine engines. However, both of these devices rely upon complicated assemblies and components. As with the previously mentioned devices, the constant exposure to corrosive environments, abrasive contaminants such as sand and mud, and larger floating debris, can lead to component failure, valve seat failure, as well as failure due to large debris being trapped within the devices. This all leads to an inherently unreliable fluid control system over the life of the vessel.
Patti's device consists of a long tubular assembly having a shutoff valve between a seawater inlet and outlet, a second shutoff valve between a freshwater inlet and outlet, and a complicated process for changing from normal operation to flushing and then back again to normal operation. Bates' device does not have anywhere near the complexity in the process of changing from normal operation to flushing and back. However, the device is dramatically more complicated, which makes it more susceptible to the failures mentioned above, and it is a much more expensive design due to the number of sliding seals and the inherent difficulty maintaining this style of seal in the presence of so many abrasive contaminants.
This leads to another problem for both Patti's and Bates' devices; the potential to have port-to-port leakage during the flushing process that cannot be easily determined, if at all. During the flushing process with an inboard/outboard marine engine both the freshwater line and the seawater pump line are pressurized. Over time, if there is wear on the seals, valve seats, or in Bates' case, the body material between the two seals, there can be port-to-port leakage. This has the potential of introducing contaminants and saltwater into the engine during the flushing cycle. Since this is not easily determined, if at all, the signs of this happening will not be apparent until there is substantial damage to the engine, exhaust manifold, or risers, all of which are very expensive to replace.
As previously mentioned, both Patti's and Bates' devices can be used with an inboard or an inboard/outboard marine engine; however, neither of these devices can be used to flush a marine engine with an outdrive pump while the engine is running and the boat is out of the water. It is very important to run a marine engine during the flushing process so that the thermostat remains open. If the engine is off, the cold flushing fluid will immediately cause the thermostat to close, which will in turn close off much of the engine to the flushing fluid thereby dramatically shortening the life of the marine engine.
Boat owners that keep their boats on lifts or davits generally prefer to remove the vessel before beginning a thorough wash down. This allows for a person to rinse the vessel's hull and outdrive while flushing the engine. Also, many commercial establishments, especially ones that are very busy, will remove vessels from the water and complete the exterior wash down and engine flushing service at another location within the establishment.
Brogdon's flushing system does not fit into the existing normal forward flow path of fluid used to flush the engine. A portion of Brogdon's system is attached to the drain or outlet of the engine; however, the normal fluid traveling from the body of water that the vessel is in, through the seawater pump, and onto the engine never passes through the flushing system. Only the flushing fluid used during the flushing cycle passes through the system. Also, the Brogdon flushing system introduces flushing fluid directly into the engine cavities and then out the engine drain in a direction that is reverse of the normal flow of fluid.
These two differences dramatically affect the overall use of the system. First of all, by placing the current flushing system in the normal forward flowing path of cooling fluid, the installation of this flushing system is as simple, inexpensive, and completely compatible with all existing inboard and inboard/outboard engines. More importantly, the Brogdon flushing system cannot be used on an inboard/outboard engine that has the seawater pump in the outdrive. There is no means by which to keep the outdrive impeller pump from overheating and melting.
The next problem, (shortcoming), is introducing flushing fluid directly into multiple parts of the engine to attempt back flush the system. Engines, especially marine engines, have a very sophisticated system designed to introduce coolant to particular parts of the engine with specific volumes. If water is introduced to various parts of a marine engine without having separate flow and pressure restrictors placed on the individual areas that being flushed, the flushing fluid will flow through the paths of least resistance and never reach many of the parts of the engine that get the hottest and/or have the most difficult deposits to remove.
The current flushing system does not suffer from this shortcoming because it introduces the flushing fluid to the marine engine in the same manner that the engine designers intended. This allows flushing fluid to travel into, through, and out of the marine engine in the same manner, pressure and volume, which the raw water travels during normal operation.
Finally, Brogdon's flushing system relies on the building of pressure to shift the shuttle valve. This is stated to be at about fifty psi. Creating this high pressure within marine engines can have dire consequences. The portions of the engine that have elastomeric seals are prone to failing when subjected to high pressures. They are even more prone to failure when subjected to high pressures in the opposite direction that they were designed to seal against.