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Generac pressure washers are powerful and reliable machines that can help you clean various surfaces around your home or business. However, like any other engine-powered equipment, they may sometimes fail to start or run properly. This can be frustrating and inconvenient, especially when you need to get the job done quickly.
Fortunately, there are some common reasons why a Generac pressure washer won’t start, and most of them can be fixed easily with some basic tools and knowledge. In this blog post, we will go over 11 possible causes of starting problems with your Generac pressure washer, and how to troubleshoot and fix them.
11 Reasons Why a Generac Pressure Washer Won’t Start
Before we dive into the details of each possible cause, here is a quick overview of the 11 reasons why a Generac pressure washer won’t start:
1. Empty gas tank
2. Bad or old fuel
3. Dirty or clogged carburetor
4. Faulty or disconnected spark plug
5. Dirty or clogged air filter
6. Incorrect or low oil level
7. Faulty or jammed starter recoil
8. Sheared or misaligned flywheel key
9. Faulty or damaged ignition coil
10. Water in the fuel or a vibrant fuel mixture
11. Choke is in the ON position
Now, let’s look at each of these reasons in more detail, and how to fix them.
1. Empty Gas Tank
This is a simple and obvious reason why your Generac pressure washer won’t start. If there is no fuel in the tank, the engine won’t get the fuel it needs to run. You can check the fuel level by looking at the fuel gauge or opening the fuel cap and looking inside the tank. If the tank is empty, you need to add fresh gasoline to it. Make sure you use the right type and quality of fuel for your pressure washer.
Recommended Read: 12 Common Generator Repairs You Must Know
2. Bad or Old Fuel
Another reason why your Generac pressure washer won’t start is that the fuel is bad or old. Gasoline can degrade over time, especially if it contains ethanol. Ethanol is a type of alcohol that is added to gasoline to reduce emissions and increase octane. However, ethanol can also attract water and form a corrosive mixture that can damage the fuel system and the engine. Ethanol can also evaporate and leave behind a sticky residue that can clog the carburetor and the fuel lines.
To prevent these problems, you should use fresh fuel with a minimum 87 octane rating (91 RON) and no more than 10% ethanol content. Ethanol-free fuel is even better. You should also consume the fuel within 30 days of purchasing it, or use a fuel stabilizer to extend its shelf life.
A fuel stabilizer prevents the fuel from breaking down and forming deposits. You should add the fuel stabilizer to the fuel when you buy it, not after it has already gone bad. You should also store the fuel in an approved fuel container that is sealed and away from moisture or combustible products.
If you find old or bad fuel in your pressure washer, you should drain it using a fuel siphon pump and dispose of it properly. Then, you should fill the tank with fresh fuel and run the engine for a few minutes to flush out any remaining old fuel from the system.
3. Dirty or Clogged Carburetor
The carburetor is the part of the engine that mixes air and fuel to create a combustible mixture for the engine. If the carburetor is dirty or clogged, it can prevent the proper amount of fuel from reaching the engine, causing it to starve and not start. Some signs of a dirty or clogged carburetor are:
- The engine won’t start or runs rough
- The engine backfires or pops
- The engine stalls or surges
- The engine emits black smoke or smells of gas
SOLUTION: To fix a dirty or clogged carburetor, you will need to remove it from the engine and clean it with a carburetor cleaner spray and a small brush. You may also need to replace the gaskets, o-rings, and jets if they are worn or damaged. Alternatively, you can buy a new carburetor and install it on the engine.
Recommended Read: Can You Clean a Generator Carburetor Without Removing It?
4. Faulty or Disconnected Spark Plug
The spark plug is the part of the engine that ignites the fuel-air mixture in the combustion chamber. If the spark plug is faulty or disconnected, it can prevent the engine from starting or running smoothly. Some signs of a faulty or disconnected spark plug are:
- The engine won’t start or runs rough
- The engine misfires or lacks power
- The engine consumes more fuel than usual
- The spark plug is wet, dirty, or damaged
SOLUTION: To fix a faulty or disconnected spark plug, you will need to remove it from the engine and inspect it for any signs of wear or damage. You can use a spark plug tester to check if the spark plug is producing a strong and consistent spark. If the spark plug is faulty, you will need to replace it with a new one that matches the specifications of your engine. If the spark plug is disconnected, you must reconnect it to the spark plug wire and ensure it is firmly attached.
Recommended Read: How To Fix Black Spark Plugs in 7 Easy Ways
5. Dirty or Clogged Air Filter
The air filter is the part of the engine that filters the air that enters the combustion chamber. If the air filter is dirty or clogged, it can reduce the amount of air that reaches the engine, causing it to run rich and not start. Some signs of a dirty or clogged air filter are:
- The engine won’t start or runs rough
- The engine backfires or pops
- The engine stalls or surges
- The engine emits black smoke or smells of gas
SOLUTION: To fix a dirty or clogged air filter, you will need to remove it from the engine and clean it with a soft brush and warm water. You may also need to replace it if it is torn or damaged. Alternatively, you can buy a new air filter and install it on the engine.
Recommended Read: How to Clean Generator Air Filter in 8 Simple Ways +Video
6. Incorrect or Low Oil Level
The oil is the part of the engine that lubricates the moving parts and prevents overheating. If the oil level is incorrect or low, it can cause the engine to seize and not start. Some signs of an incorrect or low oil level are:
- The engine won’t start or runs rough
- The engine makes loud or unusual noises
- The engine overheats or smokes
- The oil pressure light comes on or flashes
SOLUTION: To fix an incorrect or low oil level, you will need to check the oil level using the dipstick and add or drain oil as needed. You should use the right type and quality of oil for your pressure washer. You can find the oil specifications in your owner’s manual or on the engine label. You should also change the oil regularly according to the maintenance schedule.
Recommended Read: How to Fix Low Oil Pressure in Generator
7. Faulty or Jammed Starter Recoil
The starter recoil is the engine part that allows you to start the engine by pulling a cord. If the starter recoil is faulty or jammed, it can prevent the engine from starting or running smoothly. Some signs of a faulty or jammed starter recoil are:
- The engine won’t start or runs rough
- The starter cord is hard to pull or does not retract
- The starter cord is broken or frayed
- The starter recoil is cracked or damaged
SOLUTION: To fix a faulty or jammed starter recoil, you will need to remove it from the engine and inspect it for any signs of wear or damage. You may need to replace the starter cord, the recoil spring, or the entire starter recoil assembly if they are worn or damaged. Alternatively, you can buy a new starter recoil and install it on the engine.
8. Sheared or Misaligned Flywheel Key
The flywheel key is the part of the engine that aligns the flywheel and the crankshaft. The flywheel is the part of the engine that stores rotational energy and helps regulate the engine speed. The crankshaft is the part of the engine that converts the linear motion of the piston into rotational motion. If the flywheel key is sheared or misaligned, it can cause the engine to lose its timing and not start. Some signs of a sheared or misaligned flywheel key are:
- The engine won’t start or runs rough
- The engine kicks back or jerks when starting
- The engine backfires or pops
- The engine emits blue smoke or smells of oil
SOLUTION: To fix a sheared or misaligned flywheel key, you will need to remove the flywheel from the engine and inspect the key for any signs of wear or damage. You may need to replace the key if it is sheared or bent. Alternatively, you can buy a new flywheel and install it on the engine.
9. Faulty or Damaged Ignition Coil
The ignition coil is the part of the engine that generates the high voltage needed to create a spark at the spark plug. If the ignition coil is faulty or damaged, it can prevent the engine from starting or running smoothly. Some signs of a faulty or damaged ignition coil are:
- The engine won’t start or runs rough
- The engine misfires or lacks power
- The engine stalls or surges
- The engine emits black smoke or smells of gas
SOLUTION: To fix a faulty or damaged ignition coil, you will need to remove it from the engine and test it with a multimeter or an ignition coil tester. You may need to replace the coil if it is defective or burned. Alternatively, you can buy a new ignition coil and install it on the engine.
10. Water in the Fuel or an Excessively Rich Fuel Mixture
Water in the fuel or a vibrant fuel mixture can cause the engine to flood and not start. Flooding is a condition where too much fuel enters the combustion chamber and prevents the spark plug from igniting the fuel-air mixture. Some signs of water in the fuel or a vibrant fuel mixture are:
- The engine won’t start or runs rough
- The engine backfires or pops
- The engine stalls or surges
- The spark plug is wet, dirty, or damaged
SOLUTION: To fix water in the fuel or a vibrant fuel mixture, you will need to drain the fuel tank and the carburetor and replace the fuel with fresh fuel with a minimum 87 octane rating (91 RON) and no more than 10% ethanol content. You may also need to adjust the carburetor settings to ensure the proper fuel-air ratio.
11. Choke is in the ON Position
The choke is the part of the carburetor that controls the amount of air that enters the engine. The choke is usually in the ON position when starting a cold engine, as it reduces the air intake and enriches the fuel-air mixture. However, if the choke is left in the ON position after the engine warms up, it can cause the engine to run rich and not start. Some signs of the choke being in the ON position are:
- The engine won’t start or runs rough
- The engine backfires or pops
- The engine stalls or surges
- The engine emits black smoke or smells of gas
SOLUTION: To fix the choke being in the ON position, you will need to move the choke lever to the OFF position and restart the engine. You may also need to clear the excess fuel from the engine by removing the spark plug and pulling the starter cord a few times.
Recommended Read: Generator Only Runs on Choke: Causes And Expert Tips on How to Fix it
Final Words
Generac pressure washer won’t start because either there is no fuel in the tank, the fuel is bad, it has a faulty spark plug, or any of the issues mentioned above. So, what we are trying to say is that, if you have eventually diagnosed the engine and found out the cause, don’t hesitate to reach out to a professional if you can’t fix it yourself.
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