Impeding Generator Air Intake Testing

The generator air intake is approximately a 5/8” x 3” slot at the right bottom of the air cleaner cover. Impediment of the intake was determined by using an Extech HD350 Pitot Tube Anemometer to measure the pressure drop near the center of the air filter created when the generator was operating with a 3,000 watt load. An increased pressure drop would indicate the air intake was impeded. 


PVC tubing was connected to two ports of a tee fitting that was epoxied into the “weep hole” at the bottom of the air cleaner cover and secured near the center of the air filter (as shown above). An additional length of PVC tubing connected the tee to the HD350. During operation with and without the GenTent, the pressure drops with a 3,000 watt load ranged between 0.30 and 0.34 in/H2O. For reference, when approximately 20% of the air intake slot was manually covered, the pressure drop increased to 0.70 to 0.75 in/H2O. 

Intake vacuum without GenTent

In addition, throttle position was monitored by attaching a stiff wire to the throttle linkage. An increase of throttle position would indicate that it was more difficult for the generator to obtain air when supplying power to the same load. No appreciable difference of throttle position was observed with or without the GenTent installed. 

Intake vacuum with GenTent