Everything to Know About Generator Repair

First off, why do you need to know about generator repair? Can't you hire someone to do it for you?

It depends on the situation.

Let's say you've been a responsible homeowner or renter. You've researched your back-up power needs using AlltimePower's free Back-up Power Calculator. You learned the fuel source that works best for you. You've worked with a company like ours to connect with a reputable generator dealer in your area. You have plenty of fuel on hand in case of an emergency. You even called in a technician this year to ensure your generator was working optimally. After all, the season you're most likely to need that generator is fast approaching.

And what season is that?

Well, it depends on your location. In some parts of the country summers with triple digit temperatures overload the power grid with air conditioner use. In other places, cold winters cause fuel to degrade and machinery to malfunction. Hurricanes, wildfires, earthquakes and other natural disasters can create problems for your back-up energy system, too.

No matter how well you prepared you could find yourself desperate to know about generator repair. Depending on your situation, being unable to power your home and the essential items in it isn't just inconvenient. It's dangerous.

Good luck getting a technician to make fixes in the middle of a Category 3 hurricane. Taking the time to learn basic generator repair can be the difference between suffering and comfort.

But generator technicians say that when customers call in for a generator repair, it's rarely the fault of the machine, itself. Here are some things to know about fixing your generator. This way you can keep your back-up power source in tip-top shape before calling a repairman.

Generator repair in the manual

Most problems with generators occur from improper use. Read the owner's manual and ensure the generator is set up the right way. You'll also learn a lot about generator repair for your specific product.

Pay careful attention to the timeline the manual suggests having components serviced. Missing those benchmarks can cost you time, money and a functioning generator.

Is generator repair needed or did the power go out?

Technicians say it's common for people to call because they hear their generator running but don't think the power went out. A generator running for no reason is a waste of money. But how do you know if this is actually a false alarm?

First, check with your neighbors to see if their power's out. If they say yes, it's probably an outage and there is no need for a generator repair.

Another option is to see if there is electricity at your meter base. If the meter base has a blank screen, you can be sure the power is out.

Be sure your generator is on "Automatic"

The opposite can happen, too. Is your power out, but your generator isn't kicking on?

Most generator switches are in three positions: on, off and automatic. Make sure yours is on "Automatic." That will ensure your generator turns on any time there is a significant drop in power into your home.

Check your fuel source

Every fuel source has its own strengths and weaknesses. We recently, for example, wrote about the pros and cons of propane generators. We did the same for diesel generators.

No matter what fuel your generator runs on, it's important your aware of their challenges and that you're addressing them.

Take care of your fuel source, and you save yourself many a generator repair over the year. Don't and the machine will deteriorate.

Also, watch out for water from condensation in your tank. Algae can grow and cause problems. It's best to check on your tank and ensure it's full. That will help minimize contaminants.

This might go without saying, but if your generator isn't starting, don't forget to check that it has fuel. This mistake happens more than you think. Also, be sure to keep an eye out for leaks in your fuel tank.

Keep an eye on your oil

Automatic oil checks are common in portable generators. If the oil levels are low, the generator will shut itself down. Check your oil level with a dipstick and try to keep the oil level full.

You also want to stay on top of oil changes, so it doesn't contaminate your machine. Read the generator's manual to see when to change the oil.

Be mindful that the low oil sensor can malfunction. If you're running your generator on an uneven surface, for example, oil levels may misread.

It's also possible the low oil sensor is broken. To check, disconnect it by unplugging the wire that runs out of the engine's crankcase. If the generator starts after disconnecting the low oil sensor, that's the culprit, and it needs replacing.

Search for clogs

If you have a gasoline generator, you should drain the carburetor any time you're putting your generator into storage for a month. This is because old gasoline will form clogs that stop new fuel from getting through.

To clean the carburetor, close the fuel valve. Remove the bowl at the bottom of the carburetor. Use a brush and towels to clean out any fuel debris. Utilize a sewing needle or safety pin to clean out the brass jet nozzle. Then turn the fuel valve on before trying to start the generator again.

Your fuel valve can also become clogged. To check for that, unplug the hose from the inlet side of the fuel valve. Now you can see whether gasoline is able to flow through the fuel line.

Control your generator's temperature

What should the temperature of your generator be? Some of that answer depends on your source.

With propane, for example, if the generator gets hot it will cease to function. That's a safety feature.

Keep an eye on the temperature gauge. Anything over 200 degrees Fahrenheit is likely to be too hot and cause a problem. If the temperature is climbing, check coolant levels after the generator has cooled. Refill the coolant if necessary.

Is your battery dead?

If you're using a portable generator instead of a standby generator, this is one of the most common issues you may face.

Generators work by moving electrical conductors though a magnetic field. Residual magnetism is required to start your generator. If it's lost, the generator won't be able to produce power to initiate.

These are three ways residual magnetism disappears:

  1. The generator isn't used for a while.
  2. The load is connected, but your portable generator is off.
  3. You've run a generator without a load for too long.

When your generator is running, a load should be connected to it. Before you shut your generator off, turn off the switch or breaker to disconnect the load.

Adjust the choke

The choke controls the amount of air that's flowing into the carburetor during start-up. Is your generator trying to start, but the engine won't turn over? The problem may be too much or little air mixing with your fuel during combustion.

When you start a generator that hasn't been running over the past few hours, the choke should be closed. It's the "start" position on most generators. Once the generator warms up, the choke can gradually be moved toward open or "run."

If your generator has been off for only a short while, the engine is warm. The choke will need to be halfway to fully open when starting the generator.

If your engine can't turn over, it might be because you aren't operating the choke controls correctly.

Clear your air filter

It's important to keep the area around your generator clear of debris. Generators have been known to suck in trash, brush and tree limbs. This can get stuck in your air filter and can stop your generator from working. Before you a call a technician, check to see if an animal has gotten into your generator or chewed through a cord. Make sure trash isn't stuck inside, either.

Did adjusting the choke as mentioned in the previous step seem to help, but not quite solve the problem? The air filter might be to blame. If your air filter is blocked, your carburetor won't receive air for combustion.

Examine your spark plug

If the engine doesn't turn over during start-up, your spark plug might be the problem. To check, remove it from the engine with a spark plug socket. If the spark plug has either deposits that can't be cleared with a brush, cracked porcelain or broken electrodes, it needs to be replaced.

If it doesn't need to be replaced, clean any debris with a brush and adjust the electrode gap as explained in your user manual.

You can confirm the spark plug is working by holding it against the engine's crankcase while pulling your generator's recoil starter. A working spark plug will produce blue sparks. If it does, return the spark plug to the engine and try restarting it.

Check the load

One of the first steps in choosing a generator is to understand your back-up power needs with AlltimePower's free Back-up Power Calculator. Too many customers try to save money by buying a generator that is too small. But if it can't produce the needed power, the generator overloads.

What many don't understand is an appliance or device uses five times more power in its "start phase" than its "operating phase."

If you calculate your power load based on operating capacity instead of initiation capacity, the generator might not start.

One way to avoid this problem is to purchase a generator that can meet your power needs based on your total starting capacity. Another, less expensive, option would be to unplug some of your devices and appliances temporarily. Give one wave of your appliances time to settle into operating mode before plugging in the next.

Unplug your cables

Here's an easy to solve problem. Your generator won't start if there are cords plugged into the outlets on your generator. Whenever starting the generator, you shouldn't have anything plugged in. That includes extension cords that don't have appliances attached to the other end.

Replacing fuses and resetting circuit breakers

Is your generator running without generating power? There's a chance it blew a fuse or tripped a circuit breaker. You can solve the problem by resetting the breaker and replacing blow fuses.

Prevent this from happening again by working out what caused them to trip or blow in the first place. Two common reasons this happens is an overloaded circuit or a short circuit.

1. Overloaded circuit

An overloaded circuit is the most common reason a circuit breaker trips. This occurs when a circuit is trying to draw a larger electrical load than it's designed to carry.

The circuit breaker or fuse is sized to match the load-carrying capacity of the wires in the circuit. Before the circuit wires can heat to a dangerous level, the breaker will trip. This renders the circuit inactive and will remain dead until you return the breaker lever to the "On" position.

Before you turn it on, however, you should ensure you're not putting too heavy a load on your system.

2. Short circuit

A more serious reason for a breaker tripping is a short circuit. A "hard short" is caused when the hot (black) wire touches one of these three things:

  1. Neutral (white) wire
  2. Bare Ground wire
  3. The case of a metal box

A short circuit allows for a sudden unimpeded flow of electricity due to lowered resistance. That sudden increase in current flow causes the breaker to trip.

You'll know it's a short circuit when a circuit breaker trips immediately after you reset it.

Shorts can also occur because of a wiring problem in an appliance or device plugged into an outlet along the circuit. That can be hard to find.

As you can see, the cause of a short circuit can be difficult to diagnose. Depending on your skill level, you may need to call in a professional electrician.

Check voltage and amperage

Your user guide should tell you how much voltage and amperage this generator produces. Use a voltmeter and an ammeter to confirm that's the case. If it's not, there's likely an internal issue -- perhaps the motor is damaged.

You'll likely need to call a professional to solve the problem.

But don't let it get to that point. Do proper and timely servicing of your generator. Know the running life of its key components and replace them on schedule.

It can pay to call a pro

Things will come up that you can't handle on your own. AlltimePower can help you find a professional in your area to help you service your generator.

Don't wait until the next snow storm, heatwave or hurricane, though. Get your generator serviced regularly. That way you'll have a reliable back-up power source ready to go when the next force of nature rolls into town.

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