jcb JS300 Service Manual page 910

Loss of Fast Speed
Carry out the following tests:
Test 006 Testing operation of main hydraulic spool
Test 008 Testing engine speed settings
Test 012 Testing track motor relief valve settings
Test 014 Testing track motor speeds and pressure
switches.
Machine Selects Fast Speed Travel
Carry out the following tests:
Test 015 Checking servo pressure and solenoid
voltage.
Swing Bearing Faults
Carry out the following tests:
Test 017 Checking Swing bearing vertical lift and
backlash.
E-249
Hydraulic System Fault Finding
9813/5100-1
Section E - Hydraulics
Fault Finding Tests
E-249