Trackmobile 95TM Won’t Lift: Hydraulic Pump Diagnosis and Replacement

A recent Trackmobile 95TM service call involved an older machine whose hydraulic system would not lift the unit properly. Mondak Equipment & Hose performed the diagnosis and repair in the field.

The job required hydraulic-pressure testing, pump replacement, proper pump priming, pressure adjustment and temperature monitoring. The goal was not simply to install a pump. The goal was to determine why the machine would not lift and verify that the complete system operated correctly after the repair.

The Original Problem

The Trackmobile’s hydraulic system was not producing enough lifting force. Several components can create this type of complaint:

• Low hydraulic-fluid level
• Restricted pump inlet
• Worn hydraulic pump
• Incorrect relief-valve setting
• Internal leakage
• Control-valve problems
• Damaged hoses or fittings
• Mechanical problems in the pump drive
• Contaminated or incorrect hydraulic fluid

A weak hydraulic function does not automatically prove that the pump has failed. Pressure testing is necessary to determine what the system is actually producing.

Hydraulic-Pressure Testing

The technician connected test equipment to the hydraulic circuit and deadheaded the appropriate valve to measure system pressure.

The initial testing found approximately 300 PSI at idle and more than 750 PSI as engine speed increased. Those readings were not enough for the machine to perform its required lifting functions properly.

The technician also checked component temperatures. The hydraulic pump was warming up, and the machine’s compressors were becoming hot very quickly.

Pressure and temperature information help show what is happening inside the system. Low pressure can indicate that the pump is unable to produce the required output, but it can also result from oil bypassing through a relief valve or another internal leak.

Excessive heat can be another important clue. Hydraulic energy that is lost through restriction or internal bypass is often converted into heat instead of useful work.

The test results supported moving forward with hydraulic-pump replacement, but the job still required more than removing one component and installing another.

Accessing the Hydraulic Pump

The pump on this Trackmobile was mounted in an area that required substantial disassembly to access safely.

The hood sections were removed first. The batteries were disconnected and removed from their compartment. Fluid containers were moved out of the work area, and the forward floor plate was unbolted.

Because of the floor plate’s size and location, lifting equipment was used to remove it together with the battery box. This created the working space needed to reach the pump and its hydraulic connections.

A drain pan was positioned beneath the transmission area before the pump lines were opened. The inlet, outlet and case-drain lines were disconnected and capped to control fluid loss and keep contaminants out of the system.

The upper and lower pump-mounting bolts were then removed, allowing the hydraulic pump to be taken out.

Inspecting More Than the Failed Component

With the pump removed, the technician inspected the shaft adapter collar, its bore and the visible internal areas of the gear case.

Evidence of rust was found in a pattern consistent with the machine having sat unused for an extended period. That observation was important because long periods of inactivity can affect more than the hydraulic pump.

Moisture, surface corrosion, seal condition and a loss of oil film can all become concerns when older equipment remains parked. A machine may still start and move after sitting, but components can deteriorate during the inactive period.

The top of the transmission, pump-adapter mounting plate and hose connections were cleaned before installation. These areas are difficult to clean after the pump is back in place, and dirt around open hydraulic connections creates an unnecessary contamination risk.

The new pump and fitting kit were inspected before installation to confirm fitment and review the installation requirements.

Installing and Priming the Replacement Pump

The necessary fittings were lubricated and installed. The mounting gasket was prepared, and the pump was positioned on the gear case and torqued into place.

The outlet connection and O-ring boss fitting were reinstalled. The hydraulic tank was then drained through the case-drain connection using a temporary valve and hose.

After draining, the temporary setup was removed. A quick-connect was installed inline on the tank side of the case-drain circuit.

That quick-connect provides a practical connection point for future hydraulic testing and service. A permanent diagnostic port can reduce the amount of disassembly required the next time system performance needs to be checked.

The pump inlet and case-drain lines were connected. Before startup, the pump’s priming plug was removed and the replacement pump was primed with hydraulic oil.

Priming is a critical step when installing a hydraulic pump. Starting a dry pump can prevent it from developing suction immediately and can damage internal components before oil reaches them.

After priming, the plug’s O-ring was lubricated and the plug was reinstalled.

Initial Startup and Pressure Adjustment

The batteries were cleaned and positioned near the floor opening so the machine could be started before full reassembly.

During the initial startup, the technician inspected the pump and connections for leaks. The hydraulic functions responded, confirming that the pump was moving oil and that the system was operating again.

However, basic movement alone was not enough to complete the repair.

A pressure gauge was connected at the front hydraulic coupler. The relief pressure was set to 1,500 PSI, and pump pressure was set to 1,250 PSI based on the service work performed on this machine.

The system was then tested again. The hydraulic functions operated well, and the reservoir was refilled to the correct level.

Setting and verifying pressure protects both performance and component life. Pressure that is too low may prevent the machine from lifting or applying sufficient force. Pressure that is unnecessarily high can increase heat and place additional stress on hoses, seals, valves and other components.

Pressure should be measured and adjusted with proper test equipment, not estimated from how the machine feels.

Temperature Verification

After the pump replacement and pressure adjustment, the Trackmobile was allowed to operate while the technician cleaned and organized the work area.

Approximately 30 minutes later, the pump temperature was measured at about 130°F. The inlet, outlet and case-drain lines remained near ambient temperature.

Those measurements provided a useful operating baseline after the repair. The system was no longer being judged solely by whether it moved once during startup. It was monitored after running long enough for developing heat or leakage to become more apparent.

The hydraulic tank level was checked again, the machine was inspected for leaks and the removed floor plate, batteries and hood sections were reinstalled.

Final operational checks confirmed that the Trackmobile’s hydraulic system was responding correctly and the machine was ready to return to service.

Why the Verification Matters

A hydraulic-pump replacement should include more than installing the component and briefly cycling a function.

A proper repair may require:

• Confirming the original complaint
• Measuring pressure before disassembly
• Inspecting the pump drive and mounting area
• Keeping open hydraulic connections clean
• Confirming pump and fitting compatibility
• Priming the replacement pump
• Checking reservoir level
• Setting system pressure
• Testing all affected functions
• Inspecting for leaks
• Monitoring component temperature
• Rechecking the machine after it has operated

Skipping these steps can leave an incorrect pressure setting, air in the system, a contaminated connection or another unresolved problem.

It can also lead to an expensive pump being blamed for a failure somewhere else in the circuit.

Railcar-Mover Repair Requires System-Level Troubleshooting

Trackmobiles and other railcar movers combine hydraulic, pneumatic, mechanical and powertrain systems in one specialized machine. A problem in one system can affect several different functions.

Older machines may also require a different diagnostic approach than newer electronically controlled equipment. Pressure gauges, temperature readings and direct mechanical inspections remain essential when there is limited electronic information available.

Mondak Equipment & Hose repairs Trackmobile, Rail King and Shuttlewagon railcar movers. Our approach is to diagnose the system, document the findings, complete the required repair and verify performance under operating conditions.

If your railcar mover has weak hydraulics, will not lift, runs hot or has been sitting for an extended period, contact Mondak Equipment & Hose for shop or mobile equipment service.