Land Pride BH3512 manual Testing Closed Center System, Checking the Cylinders, Return Hose

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Table of Contents

Section 1: Assembly and Set-Up

Land Pride

boom, the power crowd side of the dipper stick, and both sides of the swing. If the circuit relief is faulty, it could be caused by dirt. This could be rectified by removing and cleaning the circuit relief. See instructions for Circuit Relief Valve.

Checking the Cylinders

Take a reading at idle speed, with cylinder at end of stoke. Next take another reading at high speed. If the pressure increases with speed, it would indicate a faulty cylinder.

Return Hose:

If the return hose bursts, check to see if the high- pressure line is connected to pressure port of the backhoe, or if the return hose is restricted (usually by an oil coupler).

Testing Closed Center System

On a closed center system the gauge will read the same as the tractor’s system pressure rating. (e.i. older Closed Center John Deere’s will read 2200 to 2250 PSI)

Checking a Single Circuit

If there is a loss of power on one circuit, it may be checked by actuating the valve. The pressure should drop until the end of cylinder stroke, if the pressure does

not return to the original reading, this would indicate a faulty cylinder or circuit relief. Circuit reliefs are on the down stroke of the boom, the power crowd side of the dipper stick, and both sides of the swing. If the circuit relief is faulty, it could be caused by dirt. This could be rectified by removing and cleaning the circuit relief.

Checking the Pump

If the tractor’s PSI is rated at 2250 lbs, and the gauge reads less, the tractor’s hydraulic system is faulty or the backhoe’s valve is improperly set for closed center operation. See Closed Center Hydraulic System Section.

Checking The Cylinders

Take a pressure reading at idle speed, with cylinder at end of stoke. Next take another pressure reading at high speed. If the pressure increases with speed it would indicate a faulty cylinder.

For other hydraulic problems refer to Troubleshooting Section.

Before calling your dealer, fill in the Hydraulic Testing Chart below. The chart below will enable the service man to diagnose nearly all-hydraulic problems you may be having with your backhoe. Be certain that the cylinder is at the end of the stroke when the readings are taken.

Hydraulic Testing Chart

Cylinder Function*

PSI Idle Speed

PSI Full Speed

Stabilizer - Up R.H.

Stabilizer - Down R.H.

Stabilizer - Up L.H.

Stabilizer - Down R.H.

Dipper Stick - In

Dipper Stick - Out

Swing - Left

Swing - Right

Bucket - Open

Bucket - Closed

Boom - Up

Boom - Down

* Reder to Figure 1-5 on Page 13 for Cylinder Locations.

12 BH3512 Backhoes 340-131M

7/14/08

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Contents Backhoes Table of Contents For Your Protection Important Safety InformationBe Aware Signal Words Shutdown and StorageTransport Machinery Safely Use Safety Lights and DevicesPractice Safe Maintenance Transporting the Loader and AttachmentKeep Riders Off Machinery Prepare for EmergenciesWear Protective Equipment Avoid High Pressure Fluids Hazard838-380C 838-378C818-339C 839-933C 839-932C Owner Assistance Using This ManualApplication IntroductionBackhoe Operation, Maintenance & Safety Tips Hydraulic System Requirements Assembly and Set-UpTractor Requirements Open Center SystemTable of Contents Choose the Appropriate HosingHydraulic valve can be damaged by Checking a Single Circuit Testing Procedure for Hydraulic CircuitsTesting Open Center System Checking the Cylinders Testing Closed Center SystemHydraulic Testing Chart Return HoseDipper Stick Cylinder Using Tractor Hydraulics All TractorsUsing Tractor Hydraulics John Deere Mounting The BackhoeTransport Lock Bolts Top Link Tractor Lower Links Seat Assembly Bucket InstallationLocking Bar Installation Optional Tractor Lower LinkTransporting The Backhoe Preparing For OperationOperating The Backhoe Operating InstructionsBoom Control FunctionsStabilizers Dipper Stick And BucketDipper Stick & Boom Digging SuggestionsDigging at the Correct Angle Bucket Maintenance and Lubrication MaintenanceBucket Tooth Replacement StorageBucket Pivot LubricationLubrication Bucket Cylinder Base EndBoom Cylinder Base End Boom Cylinder Rod EndBoom Pivot Boom Swing Cylinder Base End Stabilizer ArmsBoom Swing Cylinder Rod End BH3512 Specifications & CapacitiesBH35 Series Backhoes Features and Benefits Features BenefitsTroubleshooting Hydraulic System Problem Cause SolutionLoad drops when valve PerformanceIn-tpi Torque Values ChartAppendix · m Ft-lb Mm x pitch30 BH3512 Backhoes 340-131M Warranty Corporate Office PO. Box 5060 Salina, Kansas 67402-5060 USA
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