BMW B46TU Reference Manual page 38

B46TU￿/￿B48TU￿Engines
5.￿Fuel￿System
Index
A
B
C
1
2
The￿new￿B46TU￿engine￿uses￿a￿solenoid￿valve￿injector￿HDEV6￿by￿Bosch.￿Due￿to￿the￿more￿stringent
exhaust￿gas￿emission￿regulations￿required￿to￿meet￿the￿exhaust￿emission￿standards,￿technical￿changes
were￿again￿made￿to￿the￿solenoid￿valve￿injectors.￿Sorted￿fuel￿injectors￿are￿used.￿This￿means￿that￿they
are￿hand￿selected￿at￿the￿factory￿and￿tested￿for￿the￿least￿amount￿of￿fuel￿leakage.
The￿solenoid￿valve￿injectors￿HDEV5￿and￿HDEV5￿EVO￿are￿used￿in￿the￿B46￿engine.￿While￿keeping￿the
fuel￿system￿pressure￿of￿200 bar￿(2900￿psi)￿(HDEV5￿to￿HDEV5￿EVO),￿a￿reduction￿in￿pollutant￿emission
was￿achieved￿by￿changing￿the￿injection￿pattern￿and￿volumetric￿distribution.
Due￿to￿the￿fuel￿system￿pressure￿increase￿from￿200 bar￿(2900￿psi)￿to￿350 bar￿(5076￿psi),￿the￿solenoid
valve￿injectors￿HEDV6￿were￿optimized￿using￿suitable￿materials￿and￿coatings.￿The￿injection￿pattern￿and
volumetric￿distribution￿have￿not￿changed￿compared￿with￿the￿HDEV5￿EVO.
The￿repair￿instructions￿that￿are￿currently￿valid￿must￿be￿carefully￿followed￿when￿removing￿and
installing￿the￿injectors￿in￿Service.￿An￿excessive￿rotational￿angle￿at￿the￿injector￿shank,￿and￿excessive
tensile￿and￿compression￿forces￿during￿removal￿and￿installation￿can￿lead￿to￿damage￿and￿therefore￿leaks
in￿the￿fuel￿system.
Explanation
Solenoid￿valve￿injector￿HDEV5
Solenoid￿valve￿injector￿HDEV5￿EVO
Solenoid￿valve￿injector￿HDEV6￿(B46TU￿engine)
Injector￿seat
Injection￿pattern￿and￿volumetric￿distribution
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