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Section 6: Troubleshooting
BH3512 Backhoes 340-131M
7/14/08
Land Pride
Table of Contents
Slow operation and poor
Hydraulic System
performance
Engine speed too low.
Adjust RPM’s.
Defective pump.
Check pressure or replace.
Load too heavy.
Check line pressure.
Faulty main relief valve.
Clean or replace main relief valve.
Internal valve crack.
Replace valve section.
Suction line filter plugged.
Clean.
Oil too heavy for cold weather use.
Replace with lighter oil.
Power supply may not be plumbing
enough oil.
Use a flow meter to check out whether 4-8 GPM flow rate
is being achieved.
Low oil level.
Add oil.
Pressure line restricted.
Check for obstruction.
Collapsed suction line.
Check for damage.
Valve spool not at full stroke.
Check movement and linkage.
Backhoe does not hold
up load
Cylinder seals leaking.
Replace seals.
Valve spool leaking.
Replace seals.
Oil bypassing valve spool.
Replace valve bank.
Load drops when valve
spool moved from
neutral
Dirt in load check valve.
Disassemble and clean.
Excess oil heat
Damaged or worn pump.
Repair or replace.
Too fast of an engine speed.
Reduce throttle.
Main relief bypass valve improperly
set.
Check relief setting.
Draft control lever not all the way
down.
Position correctly.
Oil leakage
Valve spool seals.
Replace seals.
Loose hose fittings.
Tighten just enough to stop leakage.
Broken oil line.
Replace hose or line.
Independent Hydraulic
system pump failure
Improperly set relief valve.
Set relief at 1400 PSI.
Independent Hydraulic
system pump Noisy
Suction line filter plugged.
Clean filter.
Oil too heavy.
Use a lighter oil.
Jerky or erratic action
Air in system.
Check for loose connections and/or cycle all valves to
remove air.
Wrong type of oil.
Check tractor manual. For Independent Hydraulic System
use Type A non-foaming hydraulic oil.
Foamy oil.
Check tractor manual. For Independent Hydraulic System,
use a Type A non-foaming hydraulic oil.
Blown Return Valve
Improperly connected.
Make sure all connections are as shown in the assembly
section of this manual.
Problem
Cause
Solution
