Hi Phil,
This post, which was originally written for Phil, has been very time consuming. However, before I post it, I first want to respond to the statement made by Murle.
I will respond to all posts, given the time and when I am not out of town! The fass is what it is, a product admittedly designed by altering the blue prints to the older Fuel Preporator. The maker of the fass has already admitted in state court to having misrepresentated things. The Fuel Preporator is what it is, the original, patented product. Additionally, the Fuel Preporator AirDog, smaller and more compact, has many features including: positive air/fuel separation, low pressure warning light, a fuel return system that won't give you a fuel shower when fueling with the engine running, CARB approved for California residents, a well engineered and secure mounting system, fuel filters and water separators speciffically designed for the application and a relay controlled wiring harness to name a few. Sorry, we don't have a brace and radiator clamp to hold our pump up. Actually, our design is such that we don't need it. Please read the rest of the post to Phill and you will have more questions answered!!!
The micron rating of a filter simply states the level of filtration of a particular filter. The use of a more expensive, 'off the shelf' hydraulic filter simply because it fits, at the expense of the consumer, rather than spending the money to develop a less expensive fuel filter that accomplishes the same thing, in my opinion, merely suggests the vendors level of concern for the quality of the finished product and the consumer. It may cost more to do it right in the first place, however the effort will be rewarded in the long term. The fuel filters used on the AirDog, as on all Fuel Preporators, are designed appropriately for the application. We are working to make two micron StrataPore TM fuel filters available for the AirDog.
The Fuel Preporator was designed with full concern of the diesel engine and the operator in mind. The Fuel Preporator was designed to be a complete product. To accomplish this, it has many features. For instance, as shown in the 1998 patent there are two prominent air/vapor separation features. The first capitalizes on the fact that a filter element when submerged in a body of fluid has a natural resistance to the passage of air vapor. The entrained air/vapor is separated from the fluid as the fluid passes through the filter media. In the Fuel Preporator, the separated air/vapor is then removed by special internal features of the system and vented through the return line back to the fuel tank, its source. This feature, which gives positive air separation under all prescribed operating conditions of the appropriately applied Fuel Preporator, is not in the fass. The fass replicates identically the secondary air/vapor feature of the 1998 Fuel Preporator patent figures and drawings. This feature, which is described in detail in the disclosure and claim sections of the Preporator's 1998 patent was designed for several functions. Although one function is act as a gas exit port, under certain conditions it has limitations. A device using only this method of air separation can be made to appear to separate air/vapor from fuel on a demo stand, however, it has its limitations and under certain operating conditions can pass large volumes of vapor to the engine.
As the Inventor of the Fuel Preporator, I would not in good conscience attempt to market a device with only partial features, patented and/or unpatented features, of the Fuel Preporator. A device such as this, with such a relatively high flow and high return volumes of fuel into a small tank, such as those in use on the pickup truck, can create excessively aerated conditions that could have potentially devastating effects to the fuel system components of a diesel engine. The features of the Fuel Preporator all have their purpose. That purpose is to fulfill the complete fuel filtration and deliver needs of the diesel engine that allow the engine peak or optimum designed performance under all reasonable operating conditions. This requires the fuel to be properly filtered for the removal of contaminates, water, particulates and especially entrained air/vapor. Until Fuel Preporator, lost power from plugged fuel filters and air/vapor entrained in fuel was a problem no one had solved! Cummins addressed air/vapor in fuel and partially filled primary fuel filters in their July 1st, 1965 Service Topic, 5-135. Caterpillar quantified it in their March 1990 Special Instruction as "normally, No. 2 diesel fuel contains about 10% air in solution, although the air is not visible... " All students of hydraulics know that if the net positive suction head at the inlet of a pump is less than that required to fill the pump, cavitation will result and vapor will be produced. When calculating the pressure head available to the fuel inlet of the average vacuum feed lift pump on the average diesel engine, it is obvious as to how cavitation develops. It should now become clear as to why diesel engines loose torque at the higher operating rpms as the fuel filter plugs from contaminates. Air and fuel vapor, as all gasses, is compressible. When present in the fuel injection system of the diesel engine, it creates a pressure-time lag in the injection that results in retarded injection timing as well as possible damage to the system components.
Diesel fuel is the lubricant to most parts of the fuel injection system. When the fuel film breaks down or is displaced by air/vapor, metal on metal conditions result. Just as when the oil film in other parts of the engine break down, the result is excessive abrasion and permanent component damage.
Air/vapor present in diesel fuel, entrained through mechanical agitation or developed through pump cavitation, creates problems. The Fuel Preporator removes the entrained air/vapor from the fuel and maintains the necessary positive pressure head to your engines system for optimum engine performance. For the 5. 9 Cummins it also has the capability to successfully replace the original lift pump. For convience we include a low fuel pressure warning light to signal necessary maintainence.
Thanks for your time Phil, I hope this will help to answer more of your questions.
Charlie
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