injector testing Flashcards
the frequency of injectors maintenance (how often) depends on what 3 major conditions?
- normal operating conditions
- quality of fuel used
- the efficiency of fuel filtering system
the pressure in which an injector opens is also called the _______ pressure
cracking pressure
for most injectors the opening pressure is in the range of _______ bars
125-175
the opening pressure of injectors is hand tested using a test unit called a?
pop tester
if atomized fuel or test fluid at a high pressure is directed towards the human body what can happen?
severe injury
injector testing is done using diesel or test fluid?
test fluid
the test to check for excessive leaking back of fuel from between the needle valve and nozzle body is called a ?
leak back test
the test in which injector pressure is held right below opening pressure to observe for drips and dribbles is called a?
nozzle seat test or dribble test
a visual check for injector spray pattern is a test called a?
atomizer operation test
abnormal spray patterns may cause what kind of build up in nozzle holes?
carbon
how long is injector pressure held below opening pressure during a dribble test?
10 seconds
if an injector fails a dribble test what may need to be done?
regrinding or renewing of needle valve or nozzle
a pressure drop from approximately 150 to 100bar in less than 6 seconds during a leak back test indicates what parts should be renewed?
either needle valve and nozzle or injector spring
