Bobcat Hydraulic Pump: Failure Symptoms and What to Do

A Bobcat skid steer runs two separate hydraulic pump systems, and which function is weak tells you which one is sick. Weak or uneven drive points at the hydrostatic piston pumps; slow lift, tilt, or attachments point at the gear pump. And before blaming either: most "failing pumps" turn out to be healthy pumps starved by clogged filters or low fluid.

Quick Facts

• Two systems: hydrostatic pumps drive the wheels; the gear pump runs lift, tilt, and auxiliaries
• The weak function names the suspect pump (symptom map below)
• Filters and fluid first: the cheapest fix is usually the right one
• Any pump swap demands a full flush plus new filters, or the new pump dies young
• Match pumps by model AND serial, never model alone

What Are the Symptoms of a Failing Hydraulic Pump?

Map the symptom to the system before spending anything:

Symptom	Likely system
Machine pulls to one side, one track or wheel pair weak	Hydrostatic pump (that side)
Sluggish drive both sides, worse when hot	Hydrostatic system, or starved supply
Slow lift or tilt, weak attachment flow	Gear pump
Whining or growling that rises with RPM	Either pump cavitating: check fluid and filters NOW
Everything weak, everything slow	Fluid level, clogged filters, or suction restriction

Cavitation noise is the one to treat as urgent: a pump screaming for oil is eating itself while you listen.

Which Pump Is It: Hydrostatic or Gear Pump?

The two systems share a reservoir but do different jobs. The hydrostatic piston pumps, driven off the engine, send flow to the drive motors; steering and travel live here, which is why a hydrostat problem shows up as drive behavior. The gear pump supplies the lift and tilt cylinders and the auxiliary circuit that powers attachments; a gear pump problem shows up as work behavior. A machine that drives fine but lifts slowly has told you which pump to look at, and vice versa.

Why You Check Filters and Fluid Before Blaming the Pump

This is the money-saving section. A hydraulic pump is a precision device that tolerates everything except starvation, and a clogged filter or low reservoir starves it. The result mimics pump failure perfectly: weak functions, heat, noise. The sequence that protects your wallet:

1. Check fluid level and condition; milky means water, burnt-smelling means overheated
2. Change the hydraulic filters if they are anywhere near interval
3. Run the machine and re-test the weak function

Our model guides, including the Bobcat 873 guide, preach the same filters-first rule for a reason: a filter costs pocket change against a pump, and it resolves a remarkable share of "pump failures."

Can a Hydraulic Pump Be Fixed?

Often, yes. The honest ladder:

• Reseal or rebuild kit: right call when the pump leaks externally or has known wearable seals but its internals measure within spec; cheapest path, requires clean disassembly skills
• Remanufactured pump: professionally rebuilt core with new wear parts; the value sweet spot for a worn pump
• New pump: the call when the case is damaged, internals are scored, or downtime costs more than the price difference

One rule overrides the ladder: if the old pump shed metal, the debris went everywhere, and whatever you install inherits it unless you flush. Consult a certified mechanic for hydrostatic pump internal work; those tolerances punish improvisation.

How Much Does It Cost to Replace a Hydraulic Pump?

The drivers matter more than any quoted figure. Which pump: gear pumps cost less than hydrostatic piston pumps. Which route: rebuild kit, reman, or new spans a wide range. Who works: the labor share depends on access, and skid steer pumps are tighter quarters on some models than others. And the hidden line item everyone forgets: fluid, filters, and the flush, which are not optional. Get quotes on a reman with your serial number in hand; that is where the value usually lands.

What Is the Life Expectancy of a Hydraulic Pump?

Thousands of hours when the oil stays clean, sharply fewer when it does not. Fluid cleanliness is the whole story: contamination is the leading killer of hydraulic pumps, which makes filter intervals and fluid changes the actual life-extension program. A pump that lives on clean oil at proper level routinely outlasts the rest of the machine's wear items; a pump run on dirty oil is a countdown.

Replacing a Bobcat Pump: The Flush Rule

When a pump fails, it seeds the entire system with debris: lines, valves, motors, cylinders, cooler. Install a new pump into that system without flushing and the debris circulates straight back through it, and the new pump fails the way the old one did. The discipline: flush the system, replace every filter, refill with the specified fluid, and only then commission the new pump. Skipping the flush to save an afternoon is how people buy the same pump twice.

Finding the Right Pump for Your Model and Serial

Bobcat revised pumps within model runs, so a 753, 763, or 773 can take different pumps depending on serial break. Ordering by model alone is a coin flip; ordering by model plus serial is certainty. Our Bobcat parts catalog lists pumps and hydraulic components with OEM cross-references, and our guide to Bobcat serial number lookup shows where to read yours. It is the customer's responsibility to verify part compatibility before purchasing; email your serial to sales@partsonline.com and our parts specialists will confirm the exact pump. For the cylinder end of the system, our hydraulic cylinder seal kit guide covers seal identification.

Safety: Pressure and Load Before Any Hydraulic Work

Lower the lift arms fully or engage the approved arm supports before working near them; never trust hydraulics to hold a load over a person. Shut down and cycle the controls to relieve stored pressure before opening any fitting, and never probe for leaks by hand, as pressurized fluid can inject through skin. Hot hydraulic oil burns; let the machine cool. These habits cost minutes and prevent the accidents that end careers.

Frequently Asked Questions

What are the symptoms of a failing hydraulic pump?

Weak or uneven drive points to the hydrostatic pumps; slow lift and tilt point to the gear pump; rising whine means cavitation. Everything-weak-at-once usually means starved supply, not a dead pump.

Can a hydraulic pump be fixed?

Frequently: seal kits handle leaks, rebuild kits handle wearable internals, and remanufactured pumps are the value option for worn units. Scored internals or a damaged case mean replacement.

How much does it cost to replace a hydraulic pump?

It depends on which pump (gear pumps cost less than hydrostats), the route (kit, reman, or new), and labor access on your model. Budget the flush, fluid, and filters as part of the job.

What is the life expectancy of a hydraulic pump?

Thousands of hours on clean fluid. Contamination is the leading killer, so filter and fluid intervals are the real determinant of pump life.

What are common Bobcat hydraulic pump problems?

One-side-weak drive from a tired hydrostat, slow lift from a worn gear pump, and cavitation from clogged filters or low fluid, which mimics pump failure and resolves with service.

Is there a rebuild kit for Bobcat hydraulic pumps?

Seal and rebuild kits exist for many Bobcat pumps, matched by the pump's part number rather than the machine model. Email your serial and we will confirm what is available for yours.

Filters first, symptom map second, serial number always. Do it in that order and you will either save the cost of a pump or buy exactly the right one.