Clutch Slipping
is a condition that occurs when the armature plate fails to engage and
rotate in synchronization with the clutch rotor. The field coil when
energized becomes an electromagnet which then magnetizes the Clutch rotor
and Armature plate. Friction and magnetic attraction cause the Armature
plate and Clutch rotor to lock together (clutch engagement) and rotate the
compressor shaft.
Clutch Slipping
specifically refers to a situation that occurs when the armature plate
fails to lock together properly with the rotor. The armature will then
tend to drag (slip) against the rotor surface. This dragging (slipping)
results in intense friction and heat. As the slipping continues, the heat
causes deformation of the armature plate. In the case of a rubber
armature, clutch slipping may lead to melting of the rubber damper and can
result in a subsequent failure of the entire clutch mechanism.
Possible Causes of
Clutch Slipping and overheating:
Liquid slugging
-will cause high shaft rotation torque. This inhibits rotation of the
armature plate and leads to slipping.
Contamination on
friction surfaces - will diminish the coefficient of friction between the
two mating surfaces and result in slipping of the armature.
Low voltage to the
field coil - causes a reduction in the strength of the magnetic field of
the field coil.
System
overpressure - will cause high shaft rotation torque. This inhibits
rotation of the armature plate and leads to slipping.
Engine harness
defective connection - may result in insufficient current being applied to
the field coil.
Finally, recharge the
system with the recommended amount of refrigerant and compressor oil.
Don’t overcharge and don’t add too much oil. Check cooling performance
before returning the vehicle to the customer, to verify that everything is
working properly and that the new compressor is doing its job.
