Fiat Kobelco EX355 Tier2, Technical Manual

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W5-3-2 EX355
ENGINE OVERHAUL
Combustion Chambers
Isuzu’s unique combustion chamber design provides
easy starting, maximum power output, and operating
economy.
Direct fuel injection is used. Each cylinder has an
injection nozzle placed precisely at the center of the
cylinder.
Intake ports generate maximum swirl effect for the
airfuel mixture. Exhaust ports provide minimum ex-
haust resistance.
Valve Arrangement
Each cylinder has 2 intake valves and 2 exhaust
valves. The intake valves use Isuzu’s unique inlet
ports to provide high efficiency and complete com-
bustion.
The exhaust valves are connected to a single exhaust
port.
Lubricating System
All moving engine parts are lubricated by a gear pump
pressure circulation system.
Oil is pumped from the crankcase through the oil filter
to the oil cooler where it is cleaned. From the oil
cooler, the oil travels to the cylinder block main oil
gallery from where it circulates to lubricate the engine
parts.
Oil jets in the oil gallery spray oil to the inside surfaces
of the pistons to provide optimum lubrication and
cooling.
Oil Pump and Oil Filter
The gear-type oil pump with relief valve is driven by
the timing gear.
A full-flow oil filter with a highly efficient paper element
is used.
If the oil filter element becomes clogged, a by-pass
valve opens to route the oil directly to the oil gallery.
Oil Cooler
Oil temperature rises as the engine warms up with a
resulting decrease in lubricating efficiency. The oil
cooler operates to maintain low oil temperature and
high lubricating efficiency. The oil cooler consists of a
body and cooling element.