Buell 2002 S3T, Service Manual

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3-34 2002 Buell S3T: Engine
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OIL PRESSURE INDICATOR SWITCH 3.10
GENERAL
The oil pressure indicator switch is a pressure-actuated dia-
phragm-type switch. When oil is not circulating through the
system or when oil pressure is abnormally low, spring tension
holds the switch contacts closed, thereby completing the sig-
nal light circuit and causing the indicator lamp to illuminate.
OIL PRESSURE
SIGNAL LIGHT
The oil pressure signal light turns ON when:
●
Ignition switch is turned on prior to starting engine.
●
Oil is not circulating through the running engine.
●
Oil pressure is abnormally low on the running engine.
●
Engine is idling far below 1000 RPM.
The oil pressure signal light turns OFF when:
●
Oil is circulating with adequate pressure through the
engine running at 1000 RPM or greater.
Troubleshooting information is listed in Table 3-8.
NOTE
If the ignition is turned back on immediately after the engine
is stopped, the oil light may not turn on right away because of
oil pressure retained in the filter housing.
OIL PRESSURE
See Figure 3-47. The oil pump is nonregulatory and delivers
its entire volume of oil under pressure to the oil filter mount.
When an engine is cold, the engine oil will be more viscous
(i.e., thicker). During start-up of a cold engine, oil pressure
will be higher than normal and oil circulation will be some-
what restricted within the oiling system. As the engine warms
to normal operating temperature, the engine oil will warm up
and become less viscous — oil pressure decreases.
When an engine is operated at high speeds, the volume of oil
circulated through the oiling system increases, resulting in
higher oil pressure. As engine speed is reduced, the volume
of oil pumped is also reduced, resulting in lower oil pressure.
To check oil pressure, use OIL PRESSURE GAUGE (Part No.
HD-96921-52A) and OIL PRESSURE GAUGE ADAPTER
(Part No. HD-96940-52A). Remove oil pressure indicator
switch and insert pressure gauge fitting. See
Figure 3-48.
Ride motorcycle at least 20 miles (32 km) at or above 50
MPH (80 KM/H) until engine oil reaches normal operating
temperature. At 2500 RPM, oil pressure will vary from 10-17
psi (69-117 kN/m
2
). At idle speed (950-1050 RPM), oil pres-
sure will vary from 7-12 psi (48-83 kN/m
2
).
Figure 3-47. Checking Oil Pressure (Typical)
Figure 3-48. Oil Pressure Indicator Switch
Table 3-8. Troubleshooting Oil
Pressure Signal Light
LIGHT PROBABLE CAUSES
Stays on at
speeds above
idle.
●
Empty oil tank.
●
Clogged feed line (ice and sludge,
freezing temperatures).
●
Air-bound oil line.
●
Grounded oil switch wire.
●
Malfunctioning signal switch.
●
Diluted oil.
●
Malfunctioning check valve (see
3.14 OIL FILTER MOUNT ).
Flickers at idle.
●
Incorrect idle speed. Malfunction-
ing or improperly installed check
valve (see
3.14 OIL FILTER
MOUNT ).
Does not glow
when ignition
is turned on
(prior to oper-
ating engine).
●
Malfunctioning signal switch.
●
Malfunction in wiring.
●
Burned-out signal bulb.
●
Dead battery (see NOTE above).
b0350x3x
6218
Oil Filter
Switch