Английский язык. Писарева Л.П. - 38 стр.

                                         Вариант II
                                            Text
                                         Maintenance

       The conditions of the cylinder bore is one of the main factors affecting the
operation of a high speed oil engine. When excessive lubricating oil consumption or
excessive blow-by is observed the cylinder heads should be removed and the cylinder
bores checked for wear. This requires accurate measurements by means of a dial
indicator gauge, since the wear is in any case only in thousandths of an inch.
       When the wear has reached the allowable maximum, the cylinder must be
rebored and resurfaced or have a new liner fitted depending on the design. In this
connection, maker’s instructions should be followed strictly, and great care must be
taken, particularly in case of reboring, to ensure that the alignment of the engine is
maintained.
       Some engines particularly highly-rated engines, or engines using unsuitable
lubricating oils, may have a tendency to form lacquer deposits on the bores. These
lacquer deposits are in nature of a hard varnish, dark brown or black. They prevent the
efficient sealing of the cylinder and by causing blow-by lead to excessive wear and
increase friction. Any such deposits noticed when the cylinder head is off, should be
carefully cleaned away, taking care not to damage the surface of the cylinder bore. On
two-stroke engines sludge and carbon deposits may tend, after a period, to foul the
ports. Access doors for cleaning, are usually provided, and the ports should be cleaned
out to maker’s instructions at periods varying from 300 to 1,000 hours according to the
design and duty. Periodic examination, particularly at major overhauls, should be made
for water leakage. If water leaks into the lubricating oil, there is a serious risk of
internal rusting and corrosion with excessive bearing wear and possibly even seizure.
Any water leaks should be cured as soon as noticed.


                                          Exercises

I.        Agree or disagree with the following statements ( Use: that’s right; that’s
          wrong; I think …; I don’t think …; to my mind …, As far as I know).

     1. The condition of the cylinder bore doesn’t affect the operation of the engine.
     2. Cylinder bores should be regularly checked for wear.
     3. In any case of wear the cylinder liner must be removed and a new liner fitted.
     4. No reboring of the cylinder is allowed.
     5. Some engines may have a tendency to form lacquer deposits on the bores due to
        the blow-by.
     6. Access doors are usually provided to remove carbon deposits from ports.




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