Fuel Injection Maintenance

End of Season Preparation
At the end of the season, it is very important to get all the methanol out from all system components. Methanol alcohol will destroy anodized aluminum fittings and will deteriorate the fuel bladder in the fuel tank. Did you ever see an aluminum fitting that has corroded from the inside out? This is from methanol when combined with oxygen when left sitting on aluminum. Or did you ever see a fuel filter so clogged with black residue that you can't force any air through it? This is from the deterioration of the fuel bladder and fuel lines. Here is the best way to save yourself a lot of headaches and money.

  • Drain all the fuel out of the tank tail. Dispose or put in a tightly sealed container to minimize the methanol acquiring moisture.
  • Remove the fuel cell from the car, wash it and the pick up tube with mild soap and rinse it with water and let dry thoroughly. After completely dry, close it up and store in a climate controlled area. Never use household cleaning agents or petroleum based additives, cleaners, or octane boosters as these will destroy a methanol bladder.
  • Remove all fuel delivery components including fuel lines, filters, pump, regulator, shut offs, and injection system
  • Disassemble your fuel rails and injector nozzles. Using your injector pulser and ultrasonic cleaner, clean and force Hyper Fuel System Lube or a high quality air tool oil through the injector nozzles, or send them to us for cleaning (recommended)
  • Clean and soak the lines, filters, fuel rails, and shut offs in fresh clean solvent such as a mild parts cleaner or mineral spirits. Blow dry and add a squirt of Hyper Fuel System Lube into the fittings. Install caps and plugs to seal.
  • Clean and lubricate your fuel pump and regulator by filling the inlet with Hyper Fuel System Lube and force through with compressed air.
  • Enjoy your off season!

Washing the Car
Before washing the car, put a scrub bag or trash bag over the airbox, breathers, power steering ECU, Mychron, and Power Commander. These are the only items that must be kept dry. Do not be afraid to spray the wiring harness electronics or the throttle bodies. Do not, however, focus the high pressure of a pressure washer on these areas. After the car is washed, use a leaf blower (or compressed air, but a leaf blower does a better job) to force remaining water out of pooling areas and to dry the components.

Air Filter and Breathers
Air Filter and Breathers should be cleaned after every event. To clean, remove (taking care not to get any dirt into the intake ports) and lightly tap to remove any large pieces of dirt. Spray with 77-507 K&N Air Filter Cleaner and let sit for 5 minutes. Hose the filter out with low pressure warm water from the inside out first, then hose off the outside of the filter. The filter should be a white/gray color when fully clean. Allow the filter to air dry. Do not use compressed air on fabric air filters as it will damage the element. It is a good idea to have two air filters if running two consecutive nights to allow the filter from the first night to dry properly. After the filter is dry, spray liberally with 77-506 K&N Air Filter Oil Spray until the filter is an even pink/red color.

Another option is use our foam pre-filter. The foam pre-filter captures almost all of the dirt before it gets to the cotton element. It is the best way to keep dirt out of the engine. Also saves time because it allows 3 races or more in between cleaning the cotton filter. We sell two versions.  600-5153 fits our flat filter air box and 600-5155 will fit oval style boxes. With the Hyper Flat Filter air box, the foam pre-filter simply rests in between the OuterWear and the paper filter. This product does not hurt horsepower. We performed many back to back dyno tests showing no loss of horsepower. Use only foam filter oil on this foam pre-filter, part number 77-260.


 

Fuel Filters
The 25 micron filter must be cleaned every 2-4 races and the 120 micron filter must be cleaned every 4-6 races. If you clean the element with an air hose, blow it from the inside out, so that the particles will be on the outside of the mesh. The best (and really the only way for the 25 micron) way  to clean your filters is with an ultrasonic cleaner. This is the same type of cleaner that jewelers use. We sell a low cost Ultrasonic Cleaner and Cleaner Fluid to go with it. Use this cleaner to clean your injector nozzles as well.

Fuel Delivery System
Electronic fuel injection systems can function so perfectly that it is easy to forget how awful it was to take apart and clean those carburetors every week. Keep the fuel injection system functioning optimally with weekly maintenance and proper off-season storage. Because methanol evaporates quickly, do not leave it in the nozzles and fuel delivery system for extended periods of time. Make sure the system (fuel lines and fuel rail) are filled with methanol during the week. Oxygen is the enemy of a properly functioning fuel injection system. Do not allow oxygen (air) to get into the system. If the car will be raced on a weekly basis, the only necessary maintenance is to clean the fuel filters at least every six races. If the car has been recently painted, or is new, clean the fuel filters every week for three races. After cleaning the fuel filters, turn the pump on to circulate the methanol and remove air.

Here is the best way to prepare the system if it is not going to be used for more than two to three weeks:

Purge Tank Method for Storage

  • fill the Purge Tank with gasoline
  • hang the purge tank from the back of the roll cage
  • turn on the pump and reduce the fuel pressure to half of what is used with methanol (generally 25 psi), to keep the spark plugs from fouling
  • turn the fuel off at the tank tail
  • remove the fuel line attached to the shut off valve of the tank
  • turn the fuel pump on for 4 seconds, this pumps most of the methanol out of the lines and into the tank
  • attach the line from the bottom of the purge tank (feed line) to the line that was connected to the tank tail shut off valve (line going to pump)
  • remove the return line at the top of the tank tail
  • hook it up to the line from the top of the purge tank
  • turn on both shut off valves of the purge tank
  • start the engine and let it run for several minutes
  • leave the gas in the entire system until ready to race again

Race Preparation

  • turn off lower shut off valve of purge tank (feed line)
  • turn pump on for 4 seconds to pump the gasoline from the lines into the purge tank
  • turn off upper shut off valve (return line) in purge tank
  • remove gasoline purge tank from roll cage and attach optional second purge tank filled with methanol, or attach both lines onto tank tail: a second purge tank eliminates the possibility of gasoline from entering the tank tail
  • turn on shut off valve on tank tail
  • if using the second purge tank, attach lines, and turn on valves
  • turn on the pump and increase fuel pressure back to pressure used with methanol
  • if using the second purge tank, start engine, let run for several minutes, then shut off valves and attach lines back onto tank tail


Gasoline is a petroleum product so it acts as a lubricant to preserve the engine, injector nozzles, pump, and the entire delivery system. It will also enable the components to last longer and stay corrosion free when the methanol evaporates. As always, when turning the engine off, turn the engine off first and then the pump. Or, preferably, hook the engine and pump up to the same switch. This insures the engine is not running with the pump off and eliminates a switch that could go bad. If the pump is turned off first, the nozzles will keep pulsing without pressure behind them and may allow air to get into the system. Whenever a liquid of any kind is in the nozzle and is allowed to evaporate (under the presence of air in the system) it will leave a fine residue behind. The injector nozzles are machined to such tight tolerances that this residue may lead to a stuck injector.