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
Summary of Contents for 4 CADDY 1999
Page 6: ...TABLE OF CONTENTS Notes __________________________ _ Page iv Repair and Service Manual...
Page 10: ...SAFETY INFORMATION Notes _________________________ _ Page viii Repair and Service Manual...
Page 26: ...SAFETY Notes _ _ ___________________________ _ Page B ii Repair and Service Manual...
Page 48: ...BODY Notes _ _ ___________________________ _ Page C ii Repair and Service Manual...
Page 56: ...WHEELS AND TIRES Notes __________________________ _ Page D ii Repair and Service Manual...
Page 72: ...SPEED CONTROL Notes _ _ ________________________ _ Page F ii Repair and Service Manual...
Page 80: ...ENGINE Notes _ _ __________________________ _ Page G ii Repair and Service Manual...
Page 94: ...FUEL SYSTEM Notes _ _ _________________________ _ Page H ii Repair and Service Manual...
Page 110: ...ELECTRICAL Notes _ _ _________________________ _ Page K ii Repair and Service Manual...
Page 120: ...ACCESSORY WIRING Notes __________________________ _ Page L ii Repair and Service Manual...
Page 148: ...REAR SUSPENSION Notes __________________________ _ Page N ii Repair and Service Manual...
Page 154: ...REAR AXLE Notes _ _ ___________________________ _ Page P ii Repair and Service Manual...
Page 158: ...PAINT Notes _ _ ___________________________ _ Page Q ii Repair and Service Manual...
Page 162: ...TROUBLESHOOTING Notes _ _ ________________________ _ Page R ii Repair and Service Manual...
Page 170: ...LIMITED WARRANTY Notes __________________________ _ Page S ii Repair and Service Manual...
Page 176: ...LIMITED WARRANTY Notes __________________________ _ Page S 6 Repair and Service Manual...
Page 178: ...GENERAL SPECIFICATIONS Notes _________________________ _ Page T ii Repair and Service Manual...
