7 Field Service Checks Your Critical Motors Need

Preventive maintenance is one of the most effective ways to improve motor reliability, reduce unplanned downtime, and extend equipment life. Yet many facilities focus on Repairs only after something goes wrong.

The reality is that most motor failures don’t happen overnight. They begin as small issues that develop gradually and can often be identified during routine Field Service inspections.

At HECO, we’ve seen firsthand how proactive inspections help facilities avoid costly failures while improving overall equipment reliability. Whether your maintenance team performs these tasks in-house or partners with a field service provider, these are seven essential checks every critical motor in your industrial application should receive.

1. Oil and Lubrication Inspections

Lubrication is one of the simplest maintenance activities and one of the easiest to overlook.

Routine inspections should include:

• Checking seals for wear or damage.
• Inspecting shaft fits for excessive wear.
• Verifying seal drain holes are clean and properly oriented.
• Confirming proper seal-to-shaft clearance.
• Draining and replacing contaminated oil.
• Cleaning oil sumps before refilling.
• Inspecting forced lubrication systems for proper operation.
• Ensuring correct quantity of grease is present in the bearing housing.

Clean lubricants help reduce friction, remove contaminants, and extend bearing life.

2. Rolling Element Bearing Inspections

Bearings often provide early warning signs of developing problems.

To avoid and identify problems, ensure proper:

• Grease type and quantity.
• Inside and outside diameter tolerances.
• Wear patterns.

Finding rolling element bearing issues early, including early signs of spalling or failure, allows repairs to be scheduled before an unexpected shutdown occurs.

3. Sleeve Bearing and Oil Seal Evaluations

Large motors commonly rely on sleeve bearings for continuous operation.

Examine the unit to:

• Measure bearing clearances.
• Inspect oil seals.
• Evaluate bearing contact patterns.

Paying special attention for signs of thrust wear or shaft movement, these inspections help ensure proper lubrication and minimize the risk of catastrophic bearing failure.

4. DC Motor Brush and Commutator Maintenance

Unlike AC motors, DC motors require routine brush maintenance.

Quarterly inspections should include:

• Removing and inspecting brushes.
• Measuring brush spring tension.
• Examining the commutator for uneven wear or imperfections.
• Cleaning carbon dust from the motor.
• Seating new brushes correctly.
• Replacing blower filters as needed.

Even a quick walk-by inspection can reveal:

• Brush arcing.
• Weak spring tension.
• High commutator bars.
• Excessive carbon buildup.

Addressing these issues early improves commutation and extends component life.

5. Dry Ice Cleaning

Contamination is one of the leading causes of insulation deterioration.

Dry ice cleaning provides an effective way to remove dirt, oil, and debris from windings without introducing moisture.

This process is especially beneficial for:

• Synchronous motors.
• Generators.
• High-value rotating equipment.

Electrical testing should always be completed before and after cleaning to verify insulation integrity, and in some cases, re-insulation may be recommended following the cleaning process.

6. Electrical Testing and Trending

Testing a motor once only tells you its condition today. Trending electrical test results over time helps identify developing problems long before failure occurs.

Critical assets should undergo electrical testing at least twice per year using technologies such as PdMA Motor Circuit Evaluation (MCE).

Trending can reveal:

• Insulation degradation.
• Rotor issues.
• Winding contamination.
• Connection problems.
• Developing electrical faults.

This data supports better maintenance planning and reduces unexpected downtime.

7. Precision Alignment

Alignment affects nearly every aspect of motor reliability.

Proper field service should evaluate:

• Shaft versus coupling alignment.
• Motor speed and alignment tolerances.
• Soft foot conditions.
• Shim quantity, thickness, and integrity.
• Magnetic center placement.

Every motor installation also presents an opportunity to establish baseline vibration and operating data for future predictive maintenance.

Proper alignment significantly reduces vibration, improves bearing life, and extends overall motor lifespan.

Why a Technical Field Service Team Makes a Difference

Many maintenance teams have experience performing routine inspections, yet complex motors and critical assets often require specialized knowledge and equipment.

A dedicated technical field service team brings:

• Extensive experience with industrial motors and generators.
• Specialized testing equipment.
• Knowledge of industry electrical and mechanical standards.
• Precision alignment tools.
• Advanced diagnostic capabilities.
• Practical recommendations to improve long-term reliability.

Acting as a holistic partner, experienced technicians understand how electrical and mechanical systems interact, allowing them to identify root causes that may otherwise be overlooked.

An Extension of Your Maintenance Team

Many facilities don’t have the time or staffing to perform every recommended inspection on every critical asset. That’s where a technical field service partner can provide value.

Rather than replacing your maintenance team, HECO works alongside it, providing specialized inspections, advanced diagnostics, alignment services, electrical testing, and reliability recommendations when additional expertise is needed.

Whether it’s supporting planned outages or responding to unexpected issues, our field service professionals help maintenance teams stay focused on what matters most: keeping critical equipment running safely and reliably.

All Systems Go

Routine inspections aren’t just maintenance tasks; they’re opportunities to prevent failures before they happen.

Schedule an on-site evaluation to learn how we can support your maintenance team in keeping your critical motors operating at their best.

Posted in Field Service