Generator services
Generator Repair & Diagnostics
Tell us what it is doing and we will tell you what it usually means. We diagnose and repair standby generators across Parker, Palo Pinto and Erath counties, including units we did not install.
Start here
What is it doing?
A standby generator is an engine, an alternator and a controller that all have to agree before your house sees power. When one of them stops agreeing, the symptom you can see from the driveway usually narrows the cause down to two or three possibilities. Find yours below, then tell us which one it is so we bring the right parts the first time.
One safety note before anything else. Do not try to power the house from a portable generator through a dryer outlet or an unswitched connection. Backfeeding energizes the utility line outside your house and is genuinely dangerous for line crews. If your transfer switch is the thing that has failed, that is the part that exists to prevent it.
Symptoms
Six failures we see most often
What the machine is doing, what usually causes it, and what we check first.
It will not start at all
No crank, or it cranks and never fires.
Usual causes
- A dead or dying starting battery. This is the most common single cause of a no-start, and a battery can test fine at rest and still fail under cranking load.
- The system left in OFF or MANUAL after a service visit or a storm, so the controller is not allowed to auto-start.
- A failed battery charger, so the battery has been slowly discharging for months while everything looked normal.
- Fuel supply: a closed valve, a regulator that has drifted out of range, or a natural gas line that cannot deliver enough volume when the engine calls for it.
- Ignition components, a fouled plug, or a control board that has lost its configuration.
What we check
We load-test the battery rather than just reading voltage, verify charging output, read the controller’s fault history, and measure static and dynamic fuel pressure at the regulator with the engine cranking.
It starts, runs briefly, then shuts down
Usually 5 to 30 seconds, sometimes right as it tries to pick up the house.
Usual causes
- Fuel pressure that holds at rest but collapses once the engine is actually running. An undersized gas line or a tired regulator shows up exactly this way.
- Low oil pressure or a low oil level shutdown, protecting the engine.
- Overheating from a blocked air intake, a debris-packed enclosure, or a wasp nest in the vents.
- Overspeed or underspeed faults, which usually point back at fuel or governor problems.
- On propane, a tank low enough that vaporization cannot keep up in cold weather even though the gauge shows fuel.
What we check
We pull the fault log first, because the controller almost always recorded what it saw. Then we watch fuel pressure live while the engine runs, check oil and coolant, and inspect the enclosure and exhaust clearances.
There is an alarm or a warning light on the controller
Red or yellow, with or without a code on the display.
Usual causes
- Yellow warnings usually mean the unit still works but wants attention: service due, low battery, exercise missed.
- Red alarms mean the system has locked out and will not start in an outage until it is cleared and the cause is fixed.
- Common triggers are low battery, service interval elapsed, low oil pressure, high temperature, overcrank and RPM sensor loss.
- Clearing the alarm without fixing the cause just resets the clock. It will lock out again, usually at the worst time.
What we check
Note the exact code before you touch anything, and tell us when you call. On most units the historical event log tells us what happened in the seconds before the lockout, which is far more useful than the code alone.
It exercises fine, but never transfers during a real outage
The engine runs on schedule. When the power actually drops, nothing happens.
Usual causes
- The exercise cycle only proves the engine starts. On most units it does not transfer load, so a transfer switch problem hides behind a perfect exercise record.
- Utility voltage sensing inside the transfer switch has failed, so the switch never asks the generator to start.
- Worn or pitted contacts, or a failed transfer coil or motor operator inside the switch.
- A control wire between the switch and the generator that has corroded, been chewed, or was damaged during other work on the house.
What we check
We test the switch the way an outage does, by simulating utility loss and watching the whole sequence: sense, start, warm-up, transfer, retransfer and cool-down. If you want the detail on how that hardware works, read our page on the automatic transfer switch.
It is running, but the house has no power
Or only part of the house has power.
Usual causes
- The transfer switch started the generator but never actually transferred the load.
- A main breaker on the generator has tripped, often after an overload event.
- A load-shedding module has dropped circuits it is supposed to drop, and the circuits you are missing were never on the backed-up list to begin with.
- Alternator or voltage regulation failure, so the engine runs but useful output does not reach the panel.
- On an essential-circuits design, the sub-panel simply does not include the circuits you are standing in front of.
What we check
We measure output at the generator and at the panel, verify transfer switch position, and check whether load shedding is behaving as designed. Sometimes the fix is a repair. Sometimes the answer is that the system was never configured to cover what you expected.
It runs, but rough, noisy, or with unstable output
Lights flicker, motors hunt, the engine surges.
Usual causes
- Restricted airflow from a clogged air filter or a debris-packed intake.
- Degraded oil, worn plugs, or a belt at the end of its life.
- Fuel delivery that is marginal rather than absent, so the engine is starved under load.
- A voltage regulator drifting out of range, which is worth taking seriously because unstable voltage damages electronics and motors.
What we check
We run the unit under a real load and measure output voltage and frequency stability rather than trusting the display. Unstable output is one failure worth shutting down for until it is resolved.
Request service
Tell us the brand and what it is doing
The more you can tell us up front, the more likely the fix happens on the first visit.
- The brand, and the model or serial number from the data plate inside the enclosure.
- Any code or alarm showing on the controller, exactly as it appears.
- Whether it still runs its exercise cycle.
- When the problem started, and whether anything changed around then: a storm, a service visit, other electrical work.
Down right now and need someone? Call (817) 381-6158. Emergency after-hours service available.
Brands
What we service
Including units another company installed, and units whose installer is no longer around.
- Generac
- Kohler / Rehlko
- Briggs & Stratton
- Cummins
- Champion
- Honeywell
We install Generac and Kohler, and we hold Generac dealer number 1033043 as an Authorized Sales and Service Dealer. That gives us factory parts and factory documentation on the brand we see most.
On other brands we work from the manufacturer’s service data and our own diagnostic equipment. If a fault needs a part we cannot source in a reasonable time, we will say so instead of leaving your unit apart on a pad while we find out.
Once it is running properly again, a maintenance plan is how you stop the same call happening in two winters.
The visit
What a diagnostic call actually involves
We read the controller before we touch a wrench. The event log usually tells us what the machine saw in the seconds before it stopped, which beats guessing. From there we work the same order every time: the starting system, the fuel path, the mechanical condition, then the electrical output and the transfer switch.
We load-test the battery instead of reading resting voltage, measure fuel pressure both static and with the engine running, and verify output voltage and frequency under real load rather than at idle. If the unit has been sitting through a long outage, the oil and filters get looked at too. A generator engine typically wants a full oil and filter change after every 50 to 100 hours of continuous running, and extended outages get there faster than people expect.
You get the findings in plain language and a written estimate before any repair work starts. If what we find is really an overdue-service problem rather than a broken part, we will tell you that, and scheduled maintenance is the cheaper answer.
Common questions
Generator repair questions
What to check before you call, what we can service, and when a repair stops being worth it.
My generator will not start. What should I check before calling?
Three things, safely, without opening anything. First, is the controller switch in AUTO rather than OFF or MANUAL? Second, is there a code or alarm on the display, and can you photograph it? Third, is the fuel valve open, or on propane, does the tank actually have fuel in it? Those three answers change what we bring in the truck. Do not attempt to bypass the transfer switch or backfeed the house from a portable unit.
Do you repair generators that another company installed?
Yes, and a lot of our service work is exactly that. Original installers move, close or stop returning calls. We start with a full diagnostic to document what you actually have and what condition it is in, then give you a clear repair estimate before any work begins.
Which generator brands do you service?
Generac, Kohler/Rehlko, Briggs & Stratton, Cummins, Champion and Honeywell. We install Generac and Kohler, and we are a Generac Authorized Sales and Service Dealer, dealer number 1033043. Knowing the brand and model before we roll matters, because it decides which parts we carry.
Why did my generator fail when it exercises every week without a problem?
Because the weekly exercise proves less than people assume. On most systems it starts the engine and runs it briefly without transferring your house onto it. It does not test the transfer switch under real conditions, it does not test the unit under load, and it does not tell you whether the battery can still deliver cranking current in February. Those are the three things that most often fail.
Is a generator repair covered under the manufacturer warranty?
It can be, if the unit is in its coverage period and the fault is a covered failure rather than a maintenance issue. Manufacturers like Generac and Kohler expect repairs to be performed and documented by a certified servicer to keep coverage intact, which is one practical reason to have brand-trained technicians do the work. We will tell you honestly which category your fault falls into.
How fast can you get someone out?
We schedule service Monday to Friday, 8:00 am – 4:30 pm, and emergency after-hours service is available. Call (817) 381-6158 if the unit is down and you need it back, and tell us the brand, the model or serial from the data plate, and any code on the controller. That usually decides whether the fix happens on the first visit.
Is it worth repairing an old generator or should I replace it?
It depends on the failure, the age of the unit and what it would cost to bring it back to a state you can trust. A battery, a regulator or a set of contacts is almost always worth fixing. A failed alternator or a cracked block on a unit that was already undersized for the house usually is not. We give you the diagnosis and both numbers, and we do not pretend a repair is a bargain when it is not.
Related
Keep reading
- Generator MaintenanceThe service that prevents most of the failures on this page.
- Maintenance PlansAnnual and bi-annual plans, with priority scheduling for members.
- Automatic Transfer SwitchesWhy a generator can run perfectly and still leave the house dark.
- Standby Generator InstallationWhen replacing is the better answer than repairing.
- Generac GeneratorsDealer #1033043, factory parts and Mobile Link monitoring.
- Contact Armored Power SystemsHours, phone, and where to find us in Santo.
Two ways to start
Which one are you?
Need a generator
We start with what has to keep running at your property — the well, the AC, the freezer, the shop — and size the system around it. You get a written proposal with the equipment, the electrical work and the site prep all in one number.
Already own one
Repair, diagnostics and scheduled maintenance for Generac, Kohler and Briggs & Stratton systems — including units another company installed. Tell us the brand and what it is doing and we will bring the right parts.