Diesel & Generator FAQs
in Houston, TX

Generators

Why won’t my generator start after a power outage?

The culprit is often a supporting system, not the engine itself.

• Battery Standby batteries self-discharge—hot weather accelerates this.

• Fuel Low/stale fuel, clogged filters, or air in the lines.

• Control panel Fault codes, tripped safeties, or an engaged E-stop.

• Breakers/valves Main breaker off, closed fuel valve.

• Fluids Low coolant or oil can trigger shutdown/lockout.

Quick checks - Verify fuel level/valves, battery voltage and connections, panel “Ready” status, breakers on, and reset E-stop if tripped. If it still won’t start, stop cranking—continued attempts can cause damage.

What preventive maintenance (PM) intervals do you recommend for standby units?

Follow your manufacturer’s schedule first; these are common best practices:

• Weekly (user) Visual leak check, fluid levels, battery terminals, controller “Ready,” log the hours.

• Monthly Exercise under load for 30–60 minutes; check air filter; test transfer (where safe).

• Semi-annual (pro service) Oil and filters (runtime dependent), fuel/cooling system inspection and treatment, electrical checks, optional load bank test.

• Annual Full inspection per OEM guidance; coolant service per analysis; valve and governor checks as specified.

Standby units that rarely run can need more attention due to moisture, fuel degradation, and battery sulfation.

How does an Automatic Transfer Switch (ATS) work?

An ATS monitors utility power and safely switches your load to generator power during an outage, then back to utility when stable.

• What it does Detects outage - starts generator - transfers load after stabilization - returns to utility when normal - cool-down - stop.

• Key parts Main contacts, control circuitry, time delays, status/aux contacts, exercise clock.

• Common issues Worn/stuck contacts, surge-damaged boards, mis-set delays, failed exercise clocks.

• Good practice Periodic functional testing and inspection per OEM guidance.

How often should I load test my standby generator?

• Monthly Exercise under load (ideally ≥ ~30% of rating) to prevent wet stacking.

• Annually Perform a load bank test near rated load (per manufacturer guidance) to confirm full capacity.

Facilities may have specific standards—check your local authority and OEM documentation.

What is wet stacking and how do I prevent it?

Running too lightly loaded allows unburned fuel to accumulate in the exhaust (black, oily residue), causing smoke and power loss.

• Prevention regular loaded exercise and proper sizing.

• Remediation extended operation at higher load and professional cleaning if needed.

Industrial Engines

What do diesel smoke colors mean?

• White Cold start (brief), coolant intrusion (sweet smell), late timing/low compression, water in fuel.

• Black Over-fueling or restricted air (filter, charge air, turbo boost).

• Blue Oil burning (rings/valve guides/turbo seals), overfilled crankcase, extended idling.

Tip - Note when it appears (start, accel, steady), smell, and load conditions—this narrows diagnosis.

Repair vs. complete overhaul—how do I decide?

Consider overall condition, runtime/hours, compression and leak-down results, oil analysis, and whether failures are isolated (e.g., injector/turbo) or systemic (multiple components, low compression, metal in oil).

• Repair fits targeted, single-component issues with healthy baseline measurements.

• Overhaul fits broad wear, recurring failures, or when bringing the engine back to spec is the goal.

We’ll test first (compression, fueling, cooling, electronics) and recommend the most cost-effective path.

What causes diesel engine overheating?

Common causes include low/degraded coolant, radiator blockage/scaling, failed thermostat or water pump, non-engaging fan/fan clutch, head gasket issues, retarded timing, and operating above rated load.

Prevention - Coolant analysis, radiator cleaning, correct coolant mix, prompt leak repair, and verifying the fan/charge-air system.

How often should I change diesel fuel filters?

Depends on fuel quality and duty cycle—always follow OEM specs.

• Primary about 250–500 hours or ~6 months

• Secondary about 500–750 hours or annually

• Severe duty (dust/construction) shorten intervals ~50%

• Standby generators change annually regardless of hours

Modern high-pressure common-rail systems are sensitive—drain water separators regularly to protect injectors/pumps.

Service Area & Scheduling

What areas does Diesel Specialists service?

From our Humble, TX facility we serve Greater Houston, including Spring, The Woodlands, Kingwood, Atascocita, Baytown, and surrounding communities. Field service is dispatched from Humble.

Should I request field service or bring equipment to the shop?

• Field Service Ideal for diagnostics, PM on stationary units, minor repairs, and situations where moving equipment is impractical.

• Shop Service Best for overhauls/rebuilds, machine-shop work, dyno testing, major component replacement, and complex diagnostics requiring specialized tooling.

We can discuss transport options if needed.

How do I reach Diesel Specialists after hours?

Call the main number: (281) 446-1230.

(For fastest help with urgent issues, please call rather than email.)

Need more help? Contact us Today!

Call us at (281) 446-1230.