Figure 2-8.Locations for taking crankshaft deflection
readings.
Most borescopes have the following basic
components:
1. Eyepiece (zoom or wide angle)
2. Scan control ring
3. Probe tube
4. Scan mirror
5. Quartz-lined lamp
6. Focus control ring
7. Other electrical accessories
As with any optical instrument, you should handle
the borescope with care to avoid damaging its lenses and
mirrors. The borescope is powered by alternating
current. So, before you first use it, be sure to read and
follow the manufacturers operating instructions. The
borescope can be inserted through any engine opening,
such as a cylinder port, to identify problems, such as
cracked pistons, cracks in the cylinder head, burned
valves, and scuffed or pitted liners. You can remove the
crankcase cover to inspect the bottom section of the
engine.
STROBOSCOPE
A stroboscope is a flashing light source used to
measure the speed of fast-moving objects. it produces
the optical effect of stopping or slowing down an object
to allow you to observe and analyze the objects motion.
Figure 2-10 shows a typical stroboscope.
A stroboscope consists of a power switch, rpm
control dial, range switch, calibration indicator light,
calibration screws, combination adjustments, reflector
lamp assembly, and other electrical accessories. For
information about the functions of the components,
consult the operators manual.
Before you use the stroboscope, be sure to read and
follow the manufacturers operating instructions. The
instrument commonly operates from a 120-volt, 60-Hz,
alternating current supply. Any change in current
frequency will affect the flashing speed and affect the
stroboscopes accuracy for speed measurements. The
stroboscope can be used to measure the speed and to
observe the motion of rotating, reciprocating, or
vibrating mechanisms. Never leave the stroboscope
unattended while it is in use. Since the stroboscope
makes a moving object appear to be standing still,
someone could be seriously injured by the apparently
stationary object.
TORQUE WRENCH
The torque wrench is used to measure an objects
resistance to turning and to provide precise tightening
Figure 2-9.Typical borescope.
2-6