Abstract: A system for diffusing exhaust gases and controlling and suppressing backfire in an industrial truck is disclosed. Exhaust gases from the truck engine are first passed through a spark arresting muffler to remove hot, solid particles from the gas stream. The gases are then routed to a diffuser which is mounted on the truck's overhead guard. The diffuser contains a venturi and an air intake manifold to mix outside air with the gas stream and complete the ignition of unburned backfire gases. The diffuser includes a transverse diffusion chamber for substantially containing and burning backfires therein and a series of thin exit pipes for dispersing the gases and quenching exiting flames produced by the backfires within the chamber.

Abstract: Apparatus for controlling fuel flow to an engine including means for disabling the operation of the accelerator pedal linkage associated with a carburetor is disclosed. The construction materially aids in preventing engine backfire. Included is a pivotable solenoid operated latch plate which forms part of an essential pivot point in the linkage arrangement and fixes the pivot point when current is flowing from the coil in engine ignition circuit.Solenoid operated means for stopping fuel to the carburetor and closing the passageway from the carburetor into the intake manifold are also shown.

Abstract: An automotive engine ignition system which prevents either deliberate or accidental backfire when the ignition switch is shut off is disclosed. Means for automatically shutting off fuel to the carburetor and for limiting distributor timing is also disclosed.