Pressure Equalizers

A lowrider aircraft setup doesn’t have to have a pressure equalizer installed but many do. It gives the setup some sound when the car is dumped down. The purpose of a pressure equalizer is to lift and dump both sides evenly when one pump is used for a end of the vehicle. A setup with two aircraft pumps would use this devise. On a setup with four aircraft pumps this would not work nor would it be necessary. Popular units come from Bendix and Pesco.

Here are two rare Pesco equalizers. The Pesco equalizers are dersired for their loud sound when in operation.

Here are two rare Pesco equalizers. The Pesco equalizers are dersired for their loud sound when in operation.

This Pesco equalizer was in great shape except for some minor dings on the data plate. The casting has the part number stamped into the equalizer if you get one that is damaged or missing.

This Pesco equalizer was in great shape except for some minor dings on the data plate. The casting has the part number stamped into the equalizer if you get one that is damaged or missing.

How Do They Work?

Here we will try our best to describe how this part works. First thing to point out, fluid can travel in both directions in a pressure equalizer. The fluid equalizers commonly used in lowriders have three ports, one input and two outputs. Fluid enters the input and slits into two chambers inside. Each of the two chambers inside are very similar to a Fenner pump head inside . Two sets of gears with close tolerances to the walls spin at the same rate at fluid passes through the equalizer. Pressure is equalized when this occurs inside the unit. Fluid travels out of the output side of the equalizer to the cylinders.

 A basic diagram of how a Pressure Equalizer works. Note that tolerances are tighter than illustrated around the gears.

A basic diagram of how a Pressure Equalizer works. Note that tolerances are tighter than illustrated around the gears.

A Pesco EQ diagram.

A Pesco EQ diagram.