Air Diverter Valve: Description and Operation

Fig. 7 - Diverter Or Air Bypass Valve W/O Pressure Relief Valve:

Fig. 8 - Diverter Or Air Bypass Valve W/ Pressure Relief Valve:

Fig. 4 - Air Pump W/ Centrifugal Filter & Pressure Relief Valve:

The diverter or air bypass valve--Figs 7 & 8--when triggered by a sharp increase in manifold vacuum, shuts off the injected air to the exhaust preventing backfiring during this richer period.

On engine overrun the total air supply is dumped through the diverter valve muffler.

At high engine speeds the excess air is dumped through the pressure relief valve located either in the pump assembly--Fig 4--or the diverter valve--Fig 8.