Thermo King KD-II SR, Manual

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65
Engine Maintenance
ENGINE LUBRICATION SYSTEM
The TK 3.74 diesel engine has a pressure lubrication
system. Oil is circulated by a trochoid type oil pump driven
by the crankshaft timing gear and has several times the
capacity required by the engine. Oil is picked up through a
suction tube with a screened inlet. Oil to the rocker arm
shaft flows through a tube on the outside of the engine and
into the head through a restrictor fitting.
Oil pressure is affected by oil temperature, viscosity and
engine speed. Subnormal oil pressures usually may be
traced to lack of oil, faulty relief valve or worn bearings.
The use of improper viscosity oil will also produce low oil
pressure shutdowns.
Engine Oil Pressure Sensor
Engine oil pressure sensor should rise immediately on start-
ing. If engine oil pressure drops below 10 ± 3 psig (69 ±
21 kPa), the sensor signals the microprocessor to stop the
engine. Refer to THERMOGUARD µP-IV Microprocessor
Controller Operations and Diagnosis Manual (TK 41087).
Engine Oil Change
The engine oil should be changed at the recommended
maintenance interval or 6 months, whichever occurs first.
Drain the oil only when the engine is hot to ensure that all
the oil drains out. When changing oil, try to make sure that
the trailer is not tipped away from the direction that the oil
is supposed to flow from the oil pan. It is important to get as
much of the residual oil out as possible because most of the
dirt particles are in the last few quarts of oil to drain out.
Refill the pan with 10 quarts (9.5 liters) and check the dip-
stick level. Run the unit, and then recheck the oil level.
NOTE: Fill the crankcase slowly so oil will not run into
the breather hose, thus filling up an open cylinder. Leave
the dipstick out to vent the crankcase while adding engine
oil.
Add oil as necessary to reach the full mark. See Specifica-
tions page for correct type of oil.
Oil Filter Change
The oil filters should be changed along with the engine oil.
Spin-on Filters:
1. Remove the filter.
2. Apply oil to rubber ring of new filter and install filter.
3. Tighten the filter until the rubber ring makes contact,
then tighten 1/2 turn more.
CRANKCASE BREATHER
The crankcase breather system ducts crankcase gases
formed in the crankcase directly to the intake elbow. Harm-
ful vapors that would otherwise collect in the crankcase and
contaminate the oil or escape to the outside, are now drawn
back into the engine and burned. The breather hose should
be inspected yearly to make sure it is not plugged.
1. Spin-On Oil Filter
2. Pressure Valve Nut
3. Oil Pressure Valve
Oil Filter Parts