IHI NIIGATA MG(L)26HLX, Инструкция по эксплуатации

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SECTION
４
- DISASSEMBLY AND REASSEMBLY
4.6 CRANKCASE ASSEMBLY
４－６－０２
4.6.2 Camshaft bearings
The camshaft bearings are pressed in and should not be removed from the
block unless inspection shows excess wear of other damage. special tools
are required to replace the bearings and should be obtained through the
Niigata office if required.
Once the camshaft has been removed (Section4.8), the bearings can be
visually inspected and measured. The procedure for measuring and the wear
limits are given in section 3.2 (Clearance and Wear Tables).
4.6.3 Main Bearings
The crankshaft main bearings are shell-type bearings of a steel-backed
copper-lead alloy with a lead-tin overlay. They are secured both
vertically and laterally in the block. Lubricating oil is provided to
the bearings through internal ports in the block. The rear ( No 1)
main bearings includes the crankshaft thrust bearings.
Disassembly and Inspection (Main Bearings)
- Two hydraulic jacks are included in the special tools for removing the
main bearing caps. One is simply a small bottle jack used to support
the weight of the cap while the retaining nuts are removed. The other
is a bolt tensioning jack assembly, consisting of many of the same
parts as the arrangement used for removing the cylinder head nuts.
- The procedure for removing the main bearings for inspection are
outlined below (refer also to comments at end of this section for the
rear main bearing and thrust bearings).
- Install the bolt tensioning jacks by supporting the jacks underneath
the main bearing studs while engaging the draw-bolts (A-2) on the
main bearing studs. The spacer (A3) is held in place during this
operation by bar A4.