DETROIT DIESEL 53
TROUBLE SHOOTING ( Needle Valve Injection ) 2.0
Clean the spray tip as outlined under Clean Injector Parts.
Replace the spray tip assembly.
NOTE: The fuel output of an injector varies with the use of different spray tips of
the same size due to manufacturing tolerances in drilling the tips. If the fuel output
does not fall within the specified limits of the Fuel Output Check Chart, try
changing the spray tip. However, use only a tip specified for the injector being
Clean the injector tip with tool J 1243.
After the possibility of an incorrect or faulty tip has been eliminated and the injector output still does not
fall within its specific limits, replace the plunger and bushing with a new assembly.
Replace the needle valve.
Replace the spring seat.
Replace the valve spring.
Replace the cracked parts.
Replace the plunger and bushing assembly.
Re-lap the sealing surfaces.
Disassemble the injector and clean the parts.
12. Assemble the gear with the drill spot mark on the tooth engaged between the two marked teeth of the rack.
August, 1972 SEC. 2.0