Iveco Marine Diesel Engines, Installation Handbook

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MARCH 2004 CONTROL TEST PROCEDURES
14.129
MARINE ENGINES INSTALLATION
In the case of a non-standard cooling system, for example keel cooling or heat exchanger systems that
have not been supplied by IVECO, the test should be carried out as follows:
■
Open and lock the engine coolant thermostat valve.
■
Prepare it to take the following measurements: temperature at engine inlet and outlet, oil temper-
ature in oil sump, seawater temperature at the heat exchangers outlets (if present), water pump
suction pressure.
■
Sail at a maximum continuous power and measure the mentioned parameters when they reach a
stable value.
The fitting efficacy is assessed in relation to the seawater temperature, considering the following allowed
limit values detailed in each engine’s technical chart.
For example: at a seawater temperature of 15 ºC, the temperature of the liquid flowing out of the
engine of 80 ºC, the oil temperature at 100 ºC if the engine allows a maximum coolant temperature
of 106 ºC and a maximum oil temperature of 120 ºC, the ambient limit turns out to be:
■
106 + 15 - 80 = 41 ˚C for the engine cooling liquid
■
120 + 15 - 100 = 35 ˚C for the oil
It is also necessary to guarantee the engine coolant pump a minimum pressure of 0.15 bar (0.7 bar at
a 95 ºC temperature for NEF engines), and to ensure that the temperature difference between the liq-
uid flowing into and out of the engine is lower than 5-7 °C, according to the type of engine. Also, it is
advisable to check that the pressure drop of the external circuit is lower than the allowed maximum
values indicated in the technical charts.
Check that the installation complies with the filling and degassings instructions, and control the coolant
tank to guarantee proper hot water pressurisation and flow.
The engine room ventilation test consists of measuring the maximum temperature by following the
steps described below:
■
Near the air suction filters.
■
Near the generator or near the engine electronic control unit.
■
Near the oil sump and the shaft whirling damper (front part of the engine)
A maximum temperature increase of 15º C in relation to the outside temperature can be allowed.
The following test consists of ensuring proper engine compartment ventilation, and it can be carried
out by controlling that the access hatches open properly and that once opened, there is no rotation
speed increase.
Suction vacuum and exhaust back-pressure tests
Measuring the suction vacuum is useless when, in most cases, the burning air is suctioned through a
standard filter directly from the engine compartment.
If a different filter has been installed or if the air is suctioned through an outside intake, it is necessary
to check the suction vacuum when the engine is running at maximum power. In the case of aspirated
engines, it should be enough to run the engine at a no-load, calibration rate.
The maximum allowed vacuum value with clean filter must be lower than the values indicated in the
technical charts.
The back-pressure must be measured according to the instructions in Section 9.