Perkins 403J-E17T Operation And Maintenance Manual page 55

M0094137-02
The Water Temperature Regulator and
Insulated Heater Lines
The engine is equipped with a water temperature
regulator. When the engine coolant is below the
correct operating temperature, jacket water circulates
through the engine cylinder block and into the engine
cylinder head. The coolant then returns to the
cylinder block via an internal passage that bypasses
the valve of the coolant temperature regulator. This
return ensures that coolant flows around the engine
under cold operating conditions. The water
temperature regulator begins to open when the
engine jacket water has reached the correct
minimum operating temperature. As the jacket water
coolant temperature rises above the minimum
operating temperature, the water temperature
regulator opens further allowing more coolant
through the radiator to dissipate excess heat.
The progressive opening of the water temperature
regulator operates the progressive closing of the
bypass passage between the cylinder block and
head. This action ensures maximum coolant flow to
the radiator to achieve maximum heat dissipation.
Note: Do not restrict the air flow. Restriction of the air
flow can damage the fuel system. Perkins
discourages the use of all air flow restriction devices
such as radiator shutters. Restriction of the air flow
can result in the following: high exhaust
temperatures, power loss, excessive fan usage, and
reduction in fuel economy.
A cab heater is beneficial in cold weather. The feed
from the engine and the return lines from the cab
should be insulated to reduce heat loss to the outside
air.
Fuel and the Effect from Cold Weather
Recommendation for Crankcase
Breather Protection
Crankcase ventilation gases contain a large quantity
of water vapor. This water vapor can freeze in cold
ambient conditions and can plug or damage the
crankcase ventilation system. If the engine is
operated in temperatures of −25° C (−13° F) or lower
, measures must be taken to prevent freezing and
plugging of the breather system. Insulated hoses and
an insulated canister assembly should be installed. A
heater unit must also be installed into the breather
system. Both measures are required to protect the
engine when working in temperatures of −25° C
(−13° F) or lower.
Fuel and the Effect from Cold
Weather
Note: Only use grades of fuel that are recommended
by Perkins. Refer to this Operation and Maintenance
Manual, "Fluid Recommendations".
Properties of the diesel fuel can have a significant
effect on the engine cold start capability. It is critical
that the low temperature properties of diesel fuel are
acceptable for the minimum ambient temperature the
engine is expected to see in operation.
Following properties are used to define fuels low
temperature capability:
• Cloud point
• Pour point
• Cold Filter Plugging Point (CFPP)
The cloud point of the fuel is the temperature at
which waxes naturally found in the diesel fuel begin
to form crystals. The cloud point of the fuel must be
below lowest ambient temperature to prevent filters
from plugging.
Pour point is the last temperature before the fuel flow
stops and waxing of the fuel will start.
Cold Filter Plugging Point (CFPP) is a temperature at
which a particular fuel will pass through a
standardized filtration device. This CFPP gives an
estimate of the lower operability temperature of fuel
Be aware of these properties when diesel fuel is
purchased. Consider the average ambient air
temperature for the engines application. Engines that
are fueled in one climate may not operate well if the
engines are shipped to colder climate. Problems can
result due to changes in temperature.
Before troubleshooting for low power or for poor
performance in the winter, check the fuel for waxing
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Operation Section
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