Spray Pattern Test

Operate injector tester with smooth, even strokes and observe fuel spray pattern. Fuel should be uniformly atomized in an even, straight pattern. An uneven spray, fuel droplets or a solid stream of fuel indicates a faulty nozzle. See Fig 1 . Clean nozzle and repeat test. If injector still fails test it should be replaced.

Fig 1: Injector Spray Patterns Injector must not drip when needle valve is closed.