If your gearbox is making noise, leaking oil, or has already failed, you've got a production problem with a clock ticking. Kelsey Machine Services has been rebuilding industrial gearboxes of all sizes and configurations for over 40 years, with the in-house machining capability and experienced technicians to restore your unit to OEM performance. Every rebuild is backed by a written 24-month warranty, and our 24/7 emergency service is answered every day of the year.
We serve industrial facilities across all 50 states, Canada, and Mexico — from food and beverage processors to wastewater treatment plants to oil and gas operations. Our structured repair process gives you full transparency: written failure analysis, itemized quote before any work begins, and complete documentation on delivery.
Types of Equipment We Repair
Parallel Shaft Gearboxes
The most common industrial gearbox configuration — used in conveyors, mixers, pumps, and general industrial drives. KMS rebuilds parallel shaft units from fractional horsepower to multi-thousand horsepower, restoring gear mesh, bearing fits, shaft seals, and housing integrity.
Right-Angle & Bevel Gearboxes
Used wherever a 90-degree power transmission is needed — mixers, agitators, cooling towers, and conveyor drives. Bevel gear sets are precision-cut and must be replaced in matched sets. We stock common configurations and can source specialty sets quickly.
Planetary Gearboxes
High-torque, compact design used in centrifuge drives, conveyors, and heavy industrial applications. Planetary units require precise carrier alignment and gear mesh setup — work that demands experience and proper tooling. We have both.
Worm Gearboxes
Used in lower-speed, high-torque applications including conveyors, packaging equipment, and valve actuators. Worm gear sets wear in a specific pattern and require careful inspection of the worm wheel bronze for pitting and wear. We rebuild or replace as needed.
Helical & Spiral Bevel Gearboxes
Smooth, quiet, and efficient — common in fans, blowers, and precision drives. Tooth geometry must be maintained precisely for proper load sharing and noise performance. Our machining capability handles the precision work these units demand.
Centrifuge Differential Gearboxes
The internal gearbox in a decanter centrifuge is a specialized planetary unit that controls scroll-to-bowl differential speed. Failure of this gearbox is one of the most common and most costly centrifuge failures. We rebuild these in-house.
Common Failure Modes We See
Gear Tooth Wear & Pitting
Progressive surface fatigue from inadequate lubrication, overloading, or contamination. Pitting starts small and accelerates — by the time you hear it, significant damage has already occurred.
Bearing Failure
The most common gearbox failure mode. Contamination, overloading, misalignment, and improper lubrication all lead to bearing failure. Vibration, noise, and heat are the early warning signs.
Seal Failure & Oil Contamination
Worn shaft seals allow oil to leak out and water or process contamination to get in. Contaminated oil destroys bearings and gear surfaces faster than almost anything else.
Shaft Damage
Bent, worn, or cracked shafts from overloading, misalignment, or impact. Shaft damage is often secondary to a bearing or coupling failure — we identify the root cause, not just the symptom.
Housing Cracks & Damage
Cast iron and aluminum housings can crack from impact, thermal cycling, or improper mounting. A cracked housing is a leaking housing — and a leaking gearbox is a failing gearbox.
Gear Mesh Misalignment
Improper gear mesh contact from worn bearings, shaft deflection, or housing distortion leads to edge loading, noise, and accelerated wear. Correcting mesh geometry requires precision measurement and adjustment.
Our Repair Process
- 01
Complete Disassembly & Inspection
Every gearbox is fully disassembled, cleaned, and inspected. We measure gear tooth condition, bearing fits, shaft dimensions, seal surfaces, and housing integrity — all documented.
- 02
Failure Analysis
We identify the root cause — not just the damaged parts. A bearing failure caused by contamination requires a different repair strategy than one caused by misalignment.
- 03
Precision Machining
Our in-house machine shop handles shaft repair, bearing housing restoration, and housing repair. We restore worn surfaces to OEM tolerances.
- 04
Component Replacement
Bearings, seals, gaskets, and worn gear sets are replaced with new components. Every component replaced is documented in the repair record.
- 05
Assembly & Alignment
Reassembly to OEM specifications with proper gear mesh setup, bearing preload, and seal installation. Alignment is verified before the unit is closed up.
- 06
Testing & Documentation
Final inspection, operational test, and complete documentation package. Your gearbox ships with a repair report, component replacement record, and our written 24-month warranty.