Case 580SR Service Manual page 331

www.maskinisten.net
2.14 FAULT FINDING
STALL TEST
Use a stall test to identify transmission, converter, or
engine problems.
TRANSMISSION PRESSURE CHECKS
Transmission problems can be isolated by the use
of pressure tests. When the stall test indicates slip-
ping clutches, then measure clutch pack pressure to
determine if the slippage is due to low pressure or
clutch plate friction material failure.
In addition, converter charging pressure and trans-
mission lubrication pressure may also be measured.
MECHANICAL AND ELECTRICAL CHECKS
Prior to checking any part of the system for hydraulic
function (pressure testing), the following mechanical
and electrical checks should be made:
Z Check the parking brake for correct adjustment.
Z Be sure all lever linkage is properly connected and
adjusted in each segment and at all connecting
points.
Z The controls are actuated electrically. Check the
wiring and electrical components.
Z Be sure that all components of the cooling system
are in good condition and operating correctly.
The radiator must be clean to maintain the proper
cooling and operating temperatures for the engine
and transmission. Air clean the radiator, if neces-
sary.
Z The engine must be operating correctly. Be sure
that it is correctly tuned and adjusted to the correct
idle and maximum no-load governed speed speci-
fications.
HYDRAULIC CHECK
Also, before checking the transmission clutches,
torque converter, charging pump, and hydraulic cir-
cuit for pressure and rate of oil flow, it is important to
make the following transmission fluid check:
Check oil level in the transmission. The transmis-
sion oil must be at the correct (full) level. All clutches
and the converter and its fluid circuit lines must be
fully charged (filled) at all times. See note below.
NOTE: the transmission fluid must be at operating
temperature of 82 - 93 °C to obtain correct fluid level
and pressure readings. Do not attempt to make
these checks with cold oil.
To raise the oil temperature to this specification it is
necessary to either operate (work) the vehicle or run
the engine with converter at "stall". (Refer to con-
verter stall procedure).
SECTION 21 - TRANSMISSION
Copyright ©
265