Alamo BUSH HOG RMB 1660 Operator's Manual page 172

Problem
Motor Runs Too Slow
(or Slows Down Under
Load)
Motor Stops (Stops
under Load)
Pump Seizure (Pump
Locks Up)
Pump Wear (Rapid
Excessive Wear)
RMB 1660 01/22
© 2022 Alamo Group Inc.
OPERATION
Possible Cause
Engine RPM too slow
Pump Drive Damaged
Logic Valve O-ring Failure
(Gear Systems)
Damaged O-ring on
Solenoid Valve
Pump Worn or Defective
Motor Damaged or
defective
Incorrect Oil in System
Air in the oil
Excessive Ground Speed
for Mowing Conditions
Excessive Internal
Leakage in pump/motor
Low Relief Valve Setting
Restrictions in the system
Lack of Oil
Inadequate or lack of pump
Prime during initial start up.
Improper assembly
Contamination
Defective Pump
Operation Section 4-50
Remedy
Tractor must be operated at the 540PTO speed
as indicated on the tachometer
Check drive shaft attachment to the tractor
Remove logic valves and inspect seals.
Replace as required
Remove solenoid valve. Replace seals as
required.
Test to confirm, Repair or replace as required
Confirm Pump is Working correctly, Check that
spindle is not locking up, Replace or repair the
motor as required
Flush and fill with proper oil per the
specifications
Locate the source of the air intake and fix.
Flush and fill the oil as required
Operator Abuse
Confirm with pressure/flow test and replace or
repair as required
Check the Setting using a pressure/flow meter
with a restrictor valve. Adjust or replace as
needed
Identified by a concentration of heat due to
crimped hydraulic line, relief valve failure or
contamination.
Repair or replace the pump or motor. Fill the
oil to the correct level and check for leaks
Pumps must be properly primed prior to initial
startup. Consult the Technical Service manual
or contact Customer Service for proper
procedures
Pump may have been reassembled incorrectly
by the dealer following a prior failure. Rebuild
or replace
Contaminants in the system will damage the
components. Repair or replace the affected
components, then flush and refill with clean oil.
Inspect the tank for debris.
Confirm defect with customer service and
replace