Handling & Replacing Diesel Injectors

Modern injectors are manufactured to exceptionally fine tolerances under clean room conditions.  

Any mishandling or contamination of the injectors or other fuel system components may result in a number of symptoms, including low power, smoking, abnormal noises or, in extreme cases, piston damage. 

NOTE: injectors that have sticking nozzles or an incorrect spray pattern will cause irreversible engine damage!

Before removing injectors from an engine, please note: 

  • The area around the injector hole, the injector itself and the pipe work should be thoroughly cleaned (remove all traces of dirt, dust, loose paint, rust, etc) 
  • As soon as the injector pipes are removed, the pipes, delivery rail and the injector should be 'capped' to prevent possible contamination 
  • Do not handle the inejctors on the tip/nozzle, and do not allow the tip/nozzle to contact any other surface 
  • Extra care must be taken when handling unit (PD) injectors. The fuel is delivered through extremely small hoes in the side of the injector body. This part of the injector should not be touched or wiped 
  • Before re-fitting injectors to a replacement engine or cylinder head, it is best to send injectors in for cleaning and testing 
  • When installing replacement injectors, they should always be kept in their protective packaging until immediately prior to fitting. 
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