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Injectors
Special tool:
(999) 6643 Puller
Replacing
1.
Make sure the injector is thoroughly clean before
removing or fitting it. Make sure no paint flakes
stick to the sealing surfaces of the pipe ends.
2.
Remove the injector. If necessary use puller 6643.
Installing
3.
Clean the copper sleeve according to instructions
next page.
4.
Push the injector into position. Fit a new outer
sealing ring with the sealing lip facing the cylinder
head.
5.
Fit the retainer and retaining nut. Tighten to a
torque of 50
±
5 Nm (5
±
0.5 Nm).
Checking
There are no prescribed intervals for checking the
injectors. They should be removed and checked
when the engine has lost some of its power or if the
exhaust emissions are unacceptable.
Injectors should be checked in an injector tester.
Check results against injector data in “Specifica-
tions”.
Concerning repairs to and maintenance of injec-
tors, refer to the instructions of the Bosch factory.
Warning!
Utmost care must be taken when testing
injectors. Fuel spray from the injector MUST
NOT be allowed to strike unprotected parts of the
body. The jet has tremendous force and skin pene-
tration could lead to blood poisoning.
6643
Testing
To be able to assess injector condition properly, one
must be aware that the different injectors have different
spray pattern and chatter. Most important is checking
the opening/adjusting pressure and tightness. Spray
pattern and chatter are difficult to assess and do not
provide any sure indication of injector condition. All
air must be removed from the injector before testing.
Pump fuel with large pump strokes in order to get max-
imum fuel flow.
