What Is an AirDog

All Diesel Engines Need a ‘State of the Art’ Fuel Filtration Delivery System!

The solution for diesel performance is the AirDog Fuel Preporator; an aftermarket diesel lift pump with integrated dual fuel filters, water separator and air removal technology.  It is the only filtration delivery system that separates air from the fuel, as well as water and particulates. This powerful fuel pump system maintains the proper pressure flow to the injection pump of your diesel pickup, eliminating cavitation and vapor. The Fuel Preporator lift pump significantly improves diesel engine performance and is one of a very few aftermarket diesel performance modifications to be CARB certified and approved for sale and use in the state of California.

Certified To Improve the Diesel Engine

The Fuel Preporator’s effectiveness has been proven over millions of truck miles and verified by EPA & CARB Certified Olsen Ecological Laboratory testing under ISO 8178 8 Mode Test criterion. Discover how the patented Fuel Preporator technology can deliver for you:

  • Increase fuel economy. (Extend fuel filter life)
  • Increase torque output. (Enjoy a quieter engine)
  • Improve throttle response. (Enjoy a smoother idle)
  • Reduce exhaust emissions. (Optimize engine performance)

Entrained Air and Vapor in Diesel Fuel Causes Retarded Injection Timing!

Air and vapor are compressible. Their presence in the injector delays the pressure buildup and the injection. The delay of the injection results in retarded injection timing. Moreover, air in the fuel, no matter how small, remains a bubble. As a consequence, the amount of air entering the injector will vary from injection to injection. The more air/vapor present in the fuel the more retarded the injection timing, the less air/vapor present the less retarded the injection timing.



The “BEFORE” spry pattern picture, shows graphically the effect of air/vapor in delaying the pressure buildup.




The “AFTER” picture, with processed fuel from the Fuel Preporator®, represents how each and every spray pattern could and should be!

Retarded Injection Timing Negatively Affects Diesel Engine Performance!

Retarded injection timing caused by the presence of air/vapor in the fuel results in: low torque or power output, increased fuel consumption, increased exhaust emissions, rough idle/wet cylinder, and poor throttle response.

Low Torque and Low Power Output: Low torque due to a delayed injection results from the fuel arriving in the combustion chamber too late for a full burn.

To fix this, the Airdog diesel fuel filtration system removes not only debris from the diesel fuel but also water and air during its two part filtration process.  This will improve the trucks performance and reduce the effects of retarded injection timing. 

Fuel Preporator® Increases Torque and Power Output!

With the entrained air eliminated from the fuel and the necessary NPSH, Net Positive Suction Head, supplied to the transfer pump, the Fuel Preporator equipped diesel engine will have a consistently timely injection and perform at peak power output and efficiency regardless of fuel filter condition. Torque rise off idle is seen to double, peak torque increases about 6% and does not fall off at the higher RPM’s as it does with the conventional ‘vacuum feed system.’

The torque curve graph was performed by the University of West Virginia, Morgantown, Engine Lab. The top curve was the Fuel Preporator/No Air. The next to top curve was the Fuel Preporator/0.5 slpm Air Injection into the fuel tank. The bottom two curves without the Fuel Preporator start dropping at the 15/1600 rpm range. The slight recovery at 1600/2200 rpm is not typical of an in-use engine. The torque curve of a Caterpillar 3306 diesel engine under controlled testing at the University of West Virginia shows the performance improvement obtained through the use of the Fuel Preporator.