E-Z-GO FLEET 1999, Руководство по ремонту и обслуживанию техника

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ENGINE
Read all of Section B and this section before attempting any procedure. Pay particular attention to all Notes, Cautions and Warnings
A_WARNINGA_
Never operate without
spark plug installed in
the cylinder not being
tested. Fuel drawn into the cylinders will be expelled
through the spark plug opening and could be ignited
by the ignition system or another source, resulting in
a fire.
7. Remove one spark plug at a time. Removing both
spark plugs may cause the engine to rotate faster
than normal indicating a false reading and could be
a severe safety problem.
8. Use the starter to rotate the engine until the compres­
sion gauge reading does not change (usually no more
than ten seconds) This is referred as a
dry
compres­
sion test.
9. Record the gauge reading.
10. Pour approximately one half ounce of thirty weight oil
in the cylinder (through the spark plug hole) and
repeat the test. Record the result. The oil added to
the cylinder will cause a temporary seal between the
piston rings, piston and cylinder wall. This is known
as wet compression.
I
NOTE
I
:hin or very thick oils may cause a false read­
ing.
11 . Compare the dry test reading with the wet test read­
ing. A higher wet test reading indicates poor ring seal­
ing or a leaking head gasket (look for oil leakage
around the head gasket). No change between the dry
and wet test indicates valve sealing problems.
All readings should be compared with the engine manu­
factures specification. Engine cylinder specifications are
usually provided for unseated rings. As a general rule,
the compression will increase twenty pounds above the
rated PSI for an engine with seated rings. Compression
readings twenty pounds below the rated PSI indicates
poor cylinder sealing.
Compression Test Readings
a) Indicates 140 psi (965 kPa) (Ref Fig. 6 on page G-
6). Compression is good and the engine may be
new or rebuilt. If the engine is new or rebuilt, the
compression will rise to approximately 160 psi
(1100 kPa) as the rings seat. If the engine has had
extensive use, a reading of 140 psi (965 kPa) may
indicate that the engine compression is in decline
and may need to be rebuilt when compression
falls to approximately 125 psi (860 kPa).
Fig. 6 Compression Gauge
b) Indicates 50 - 60 psi (345 - 415 kPa). The rings
are in very bad condition or leaking valves are
indicated. Pour approximately one half ounce of
thirty weight oil into the cylinder through the spark
plug hole and recheck. If the compression
increases 10 psi (70 kPa) or more the rings are in
poor condition. If little or no increase in compres­
sion is indicated, the valves are leaking.
c) Indicates 100 psi (690 kPa). This indication could
be an engine with many hours of use. Adding oil to
the cylinder and rechecking should cause an
increase in compression. If so, a top end overhaul
should be considered. Refer to Engine Rebuild
manual, E-Z-GO part number 27615-G01.
Page G-6
Repair and Service Manual