Technical data

16
Repair instructions
Actions for low boost pressure
● Air inlet
Check that the air inlet to the engine bay is not
blocked.
Check that the air inlet is correctly dimensioned
where appropriate, please refer to the manual.
● Air filter
Check that the air filter is not blocked.
Replace it where necessary.
● Sealing
Check sealing
The inlet and exhaust pipes and all hose unions
must not have any leaks.
Also check that the aftercooler seals against the
induction manifold.
● Throttle control (Does not apply to
TAMD72P-A)
Check that the control can move the injector
pump fuel increase lever to the maximum posi-
tion.
● Turbocharger
Check whether the rotor shaft runs stiffly or if ei-
ther the turbine wheel or compressor wheel con-
tact their housings.
Turn the wheel under light pressure, then when
applying axial force. If the wheel does not run
freely, the turbocharger must be changed or reno-
vated.
Check the wheels for damage.
WARNING! Never operate the engine if
damage to the turbocharger compressor
wheel is suspected since fragments from a
burst wheel can be sucked into the engine.
● Cleaning
In daily operation in dusty or oily air, and if the change
interval for the air filter has not been observed, the
compressor housing and compressor wheel may need
to be cleaned.
A dirty compressor wheel can cause low boost
pressure.
The compressor section can be cleaned with the turbo
still in its housing as follows:
Remove the compressor housing.
Clean the compressor housing, compressor wheel and
shield with paraffin (kerosene) or equivalent.
Install the compressor housing and measure the boost
pressure again.
If the boost pressure is still too low, check the
following.
● Injection pump
Check the injection advance and high idle speed.
Check the function of the injection pump smoke
limiter.
● Fuel supply pressure
Check the fuel supply pressure.
Change the fuel filter and any pre-filters if neces-
sary.
● Injectors
Check the opening pressure and spray pattern.
● Engine
Check valve clearance and compression pres-
sure.
● Exhaust back pressure
Check that the back pressure in the system is
not excessive. Maximum value is 15 kPa (1500
mm water pillar).
If the boost pressure still can not be accepted, the
turbocharger must be renovated or changed.