New Holland 667TA/EBF, Repair Manual

Page: 88 / 150

2-70
Issued 11-06 Bur 87519804 NA
CHAPTER 2 - 667TA ENGINE OVERHAUL
ENGINE REPAIR MANUAL
TEST ON FUEL BACKFLOW FROM THE RETURN
BS06K218 Figure 2-91
Tests on fuel backflow from the return establishes
the operating status of the injectors. The engine
s p e e d a n d p owe r a r e c o n t r o l l e d t h r o u g h t h e
injectors. The power required by the user, through
the accelerator, is converted into the quantity of fuel
injected per cycle. This in turn is converted into
microseconds of injector opening according to the
rail pressure.
NOTE: The injectors may have problems of both a
mechanical and a electrical nature. Therefore before
proceeding with the following analysis, it is wise to
rule out the presence of water in the tank and the fuel
prefilter.
BS06K219
Figure 2-92
1. INJECTOR DUCT LOCKING NUT
When the EDC7UC31 control unit warning light
comes on during acceleration and/or cold star t
trouble, make sure the following check is done.
•
Check torque of the nut (1) locking the injector
duct on the cylinder head. The torque setting is
45 - 55 Nm (33.2 - 40.6 lb.- ft.).
1