Engine Body - FAW Jiefang Automotive 485 Operation & Maintenance Manual

1. Engine body

The engine body is of gantry design.
On the top surface, there are cylinder jacket-opening and bolt holes, and additionally there
are water-hole through to cylinder cover. Near the back end, there is lube oil hole, by which the
cylinder cover is lubricated.
At the upper part of the front end face of engine body, is cast with the water-in chamber of
water pump. Flywheel casing and rear oil-seal cover are fitted at the rear end. On the bottom
surface of engine body, there are bolt-holes for bolts of main bearing, lube oil inlet, engine-oil
pump opening and bolt-holes on crankcase sump.
On the right side of engine (when viewing from front end), there are engine-oil filter,
diesel-oil filter and water-discharge valve.
In the engine body, main oil-passage and branch oil-passages are all horizontal arranged.
When disassembling the engine for repair, it is necessary to clean each oil-passage, ensuring
cleanness and smoothness. Screw plug for each oil-passage should be tight and reliable, without
oil leakage.
2. Main bearing
The main bearing is of full-support suspension design. Main bearing cap and engine body
adopt paired boreholes, with paired marks on the engine body and bearing cap. When
assembling/disassembling it, the marks should be followed and incorrect direction is not allowed.
When assembling front main bearing cover, it is important that it should be flushed with front end
face of engine body, and should not protrude; otherwise the pressing of timing gear chamber will
be influenced. When removing the main bearing bushes for cleaning, do not mistake the upper
bush and lower bush (bush with oil groove is upper bush). Crankshaft thrust-pieces are installed at
the last main bearing, each piece at upper and lower, at front and rear. The thrust-piece is subject
to axial thrust force of crankshaft. Its working surface has oil groove on it, and its back side is a
plane. When installing it, it is necessary to put the working surface towards the thrust-surface of
crank arm, and inverse direction is not allowed. Tighten it and then tap it, ensuring that the upper
and lower thrust-pieces are kept on the same plane. Then, tighten them one by one, as per
specified tightening-torque. Upon assembling of crankshaft, if turn the crankshaft by hand, at the
flywheel end, it should rotate smoothly and freely.
3. Cylinder cover
The cylinder jacket is of wet type. At the lower part of the cylinder jacket, there are two
ring-shape grooves, into each of which a rubber water-seal ring is to be fitted.. The water-seal ring
should not twist or awry, when fitted into the groove. Then, press the cylinder jacket into the
II. Engine body
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