CS-E 460 Backfire Tests

For spark ignition Engines:

(a)After completion of the endurance test of CS-E 440, functioning tests of the Engine shall be made to determine if there is any tendency for the Engine to backfire when using the normal means of starting and during accelerations effected by any reasonable means.

(b)(1) If after the completion of the endurance test, no tendency for the Engine to backfire is established, three backfires shall be produced artificially on an Engine of the same type. If, however, a tendency to backfire is established, at least twenty backfires shall be produced artificially on an Engine of the same type.

(2)If necessary, mechanical mal-adjustment shall be used to cause backfiring. Maladjustment may include the mixture setting (if applicable) artificially weakened, non-standard ignition timing, an inlet tappet adjusted to hold the valve off its seat, or crossed ignition leads.

(3)The effect of backfires occurring during starting and during running conditions shall be established.

(4)In order to qualify for approval, the Engine shall not suffer serious damage as a result of these tests.