Pressure washing your home is a great way to keep it clean and looking great.
Using a pressure washer can be dangerous if you’re not sure how to use one.
A problem many people encounter when using a pressure washer is that it won’t turn on even if it has water.
We’ll go over eight possible reasons gas-powered power washers and six reasons an electric-powered power washer won’t start and how to fix them.
Gas-Powered Pressure Washer Problems
The most common type of pressure washer uses gas to run.
Once it has gas, the pressure washer ignites it to start the engine.
It builds up air pressure and sucks in the water.
When you pull the trigger on the pressure washer gun, pressurized water bursts out of it.
Like any gas-powered machine, there are several reasons it might not start.
1. Defective Spark Plug
Gas-powered pressure washers use spark plugs just like your lawnmower or car.
The spark plug emits a spark that ignites the gas and gets the motor running.
Over time, the spark plug starts to degrade.
Its tip burns out and can’t emit a spark anymore.
Without a working spark plug, the engine has no way to ignite the gas and start.
This could be a reason your pressure washer won’t start even though it has water.
Fix: Test And Replace The Spark Plug
Before you assume the problem rests with the spark plug, you can test it.
The spark plug sits at the front of the pressure washer.
It’s often under the motor carriage.
Pull it free and inspect the tip.
Does it look burnt, or is there a missing tip?
If so, then the spark plug has deteriorated and will need replacement.
If it still has a tip or seems to be functional, then you can run a test on it.
Take an ignition tester and hook it up to the spark plug.
When you activate the tester, you should see a small spark emit from the tip of the plug.
If you do, then the plug is working.
If you don’t, then you need to replace the spark plug.
It’s good practice to replace spark plugs every year for small engines.
2. Restricted Carburetor
Another common problem that causes small engines like pressure washers and lawnmowers to have starting problems is the carburetor.
A carburetor plays an important role in the fuel system of the engine.
It draws up air that allows fuel to reach the engine and ignites it.
The problem with carburetors is that because they make contact with fuel, it’s common for them to become messy.
Sludge is a common problem for carburetors.
As a pressure washer sits in the garage unused during the colder months, the carburetor still has gas stains on it.
Over time, the gas becomes a sludge.
It blocks the carburetor and keeps air from passing through it.
This can keep fuel from entering the engine and igniting.
Fix: Clean Out Carburetor
Fixing this problem is easy.
Locate the carburetor on the pressure washer.
It’s usually at the front of the machine.
Opening it up, you may find that it has a filter.
Replacing the filter may be the only thing that you need to do.
You can also clean the filter and the rest of the carburetor to remove the sludge.
You also want to clean the area where the carburetor makes contact with the rest of the washer.
Even having sludge in that location can cause the pressure washer to fail.
Once the carburetor is completely clean, you can put it back on the pressure washer.
With a clean carburetor, the air can pass through it and bring fuel to the engine.
Your pressure washer should start.
To avoid this problem in the future, it’s always a good idea to empty the pressure washer of gas.
Then clean out the carburetor before letting it rest over the winter.
3. Defective Ignition Coil
The ignition coil works with the spark plug to start your pressure washer’s engine.
During your spark plug test, you may find that it works well.
If that’s the case, then the problem may come from the ignition coil instead.
The ignition coil sends a spark to the spark plug.
In turn, the spark plug ignites the gas to start the engine.
If the ignition coil isn’t working, then the spark plug will never receive the spark it needs to start the motor.
There are a few reasons your ignition coil isn’t working.
- Damaged or deteriorated wires
- Bent terminal pins
- Loose connections
- Signs of moisture
Fixing the problem depends on the damage the ignition coil has.
Fix: Repair Or Replace Ignition Coil
One of the first steps you should take is to test the ignition coil.
Like your spark plug, you can use an ignition tester on the coil to see if it sends a spark to the spark plug.
If it doesn’t, then you’ll want to investigate the reason.
The first thing you should inspect is its wires.
If the ignition coil’s wires have damage or look as though they’ve deteriorated, then you may need to replace them.
New wires can send a spark from the coil to the plug.
Another sign to look for is a bent terminal pin.
If it has a bent terminal pin, then the coil can’t effectively send its spark to the plug.
In some cases, you can replace the terminal pin with another.
A loose connection is another problem you can fix.
Through the use of your pressure washer, a connection may have become loose.
Tighten the connection, and your pressure washer should come back to life.
Finally, look for signs of water damage.
Ignition coils will not work if they’re exposed to water or other liquids.
Considering that pressure washers use water, there’s a good chance the coil received water damage.
In this case, you may need to completely replace the coil.
Test the coil again to see if it’s sending a spark to the spark plug.
Replace the coil as necessary.
4. Broken Flywheel Key
One of the safety features that your pressure washer has is a flywheel key.
It’s a small part that attaches to the crankshaft.
When the engine faces a threat, the flywheel key detaches itself from the crankshaft.
It automatically turns off the engine to protect it and anyone using the machine.
The problem with a flywheel key is that it can sometimes break on its own.
When that happens, the crankshaft won’t work, and the engine won’t start.
Fix: Replace The Flywheel Key
The solution is simple.
You only need to replace the flywheel key.
The hardest part is finding it on the crankshaft.
It’s a small piece that sticks out at the base of the shaft.
If it isn’t there, then it fell out somewhere.
If it’s still attached, then check it to see if it has any damage.
Even if a small part of it is missing, it can interfere with the crankshaft’s operation.
Remove the flywheel key and replace it with a new one.
To get it into place, use a wooden hammer or similar tool to gently guide it into place.
When you start the engine, the attached flywheel key will allow the crankshaft to function.
The engine will start.
5. Broken Fuel Pump
Another vital part of your gas-powered pressure washer is the fuel pump.
It plays an important role in transferring fuel from the tank to the fuel rail.
The rail then delivers the fuel to the various injectors and into the engine combustion chamber.
If the pump isn’t working, then fuel will never enter the engine to start it.
There are a few different ways that a fuel pump can break.
One of the most common is overheating.
Some pumps rely on the presence of gas to keep themselves cool.
If you ever ran the pressure washer until it ran out of gas, then there’s a good chance that the pump overheated.
Without gas, the pump has no way of cooling itself.
When it overheats, it can break.
Contamination is another reason that fuel pumps fail.
Dirt, rust, and other debris can enter the pump through the gas tank.
Although the gas will go through a filter, it still passes through the pump first.
That debris can clog it and break it.
One final way pumps often fail is the deterioration of their gears.
Like any moving part, the gears will wear out with time.
When that happens, the pump is unable to operate itself.
Fix: Replace The Fuel Pump
In some cases, you may only need to clean the fuel pump.
Remove the fuel pump from the pressure washer and inspect it.
Look for sludge, rust, or any other kind of crust that may be causing it problems.
Then clean it and replace it.
This may fix the problem of your pressure washer not starting.
If it doesn’t, then check for damage.
If the gears aren’t working, then you’ll see noticeable signs of damage.
They may have chips or even look burnt.
The pump may also carry scorch marks from overheating.
In this case, you need to replace the pump.
With a new pump, the pressure washer will start.
6. Engine Is Too Hot
Some gas-powered pressure washers won’t start again until the engine cools down.
It’s a safety feature that protects the engine from overheating.
It doesn’t mean anything is wrong with your washer.
The engine only needs time to cool down.
Fix: Let The Engine Cool
Place your pressure washer in a shady area.
This can speed up the cooling process.
Then let the engine cool for at least an hour.
On hot summer days, it may take longer.
Once the engine is cool enough, it should start without any problems.
7. Clogged Fuel Filter
The fuel filter is another important part of your pressure washer.
The filter is responsible for catching debris and dirt from entering the engine.
If dirt or other debris enters the combustion chamber, then it could harm it.
A clogged fuel filter makes it difficult for fuel to pass through it.
That can make receiving enough fuel to start the engine impossible.
Fix: Clean The Filter
You should always clean your fuel filter before storing your pressure washer for the winter.
Remove it from the unit and hose it down.
Let it air dry, then return it to its proper place inside the washer.
With a fresh fuel filter, the fuel has an easy time passing through and reaching the combustion chamber.
8. Old Oil And Oil Filter
A gas-powered pressure washer also requires oil to run.
Without it, the engine can overheat, and its parts can be destroyed.
Oil is a lubricant that keeps the engine running smoothly.
If you have old oil in your pressure washer, then it may be unable to enter the engine.
Old oil becomes sludgy over time.
It’s unable to lubricate the engine which can destroy it and keep it from starting.
Fix: Change The Oil
You need to change the oil in your pressure washer at least once a year.
It keeps the oil fresh and is able to lubricate the engine without a problem.
It’s also a great time to clean out the oil filter and prevent the buildup of oil sludge.
With fresh oil in the engine, the washer will start without any problems.
Electric-Powered Pressure Washer Problems
A pressure washer that uses electricity instead of gas to start has its own problems.
Look for these problems and apply their fixes to start your pressure washer.
1. Connected To The Wrong Type Of Outlet
One reason the pressure washer won’t start is that the outlet doesn’t provide enough power.
Most pressure washers require 12 to 14 amps of power.
Not all outlets can provide that amount.
The result is an engine that doesn’t start or sputters.
Fix: Find The Right Outlet
Look for an outlet that uses three prongs.
These outlets deliver higher power than those with only two prongs.
Once it has enough power, the pressure washer will start.
2. Faulty Capacitor
You can tell if the capacitor on your pressure washer is going bad by listening to the motor.
If the engine doesn’t start but you can hear a humming sound, then it’s a failed capacitor.
Without it, the engine won’t start.
Fix: Replace The Capacitor
You can test the capacitor to see if it’s working.
If not, then replace it.
Once you have a new capacitor in place, the engine can start.
3. Ground Fault Circuit Interrupter Trips The Circuit Breaker
All electric power washers use grounding to keep the unit and the user safe.
The problem with the grounding is that it can trip your circuit breaker.
Since a pressure washer requires a large amount of power to work, you may blow a circuit if you have other appliances running, too.
A tripped circuit means you can’t get power to your pressure washer.
It won’t start even if you have the water on.
Fix: Reduce Power Usage In The Home
To avoid the pressure washer tripping the circuit breaker, you need to ration your power usage.
Any time you intend to use the washer, turn off the other appliances in your home.
Wait to run the dishwasher or washing machine.
With fewer high-powered appliances in use, your pressure washer won’t trip the circuit breaker and can start.
4. You’re Using The Wrong Extension Cord
Electric pressure washers work most effectively on extension cords shorter than 25 feet.
Anything longer than that won’t be able to deliver enough power to the washer.
It can make the engine fail to start.
Fix: Switch To A 12-Gauge Wire Extension Cord
If you need a longer extension cord, then it needs to be a 12-gauge wire cord at the very least.
The 12-gauge can handle delivering the power a pressure washer needs over a long distance.
With the right extension cord attached to it, the pressure washer will start.
5. Clogged Air Line
Failing to prime your pressure washer can cause the air line to clog.
A clog can also form at any time.
With a clog in the air line, the pressure washer won’t start as a safety precaution.
Prime the washer to get it working again.
Fix: Prime The Air Line
Attach the inlet to a water source.
Then double-check that the pressure washer is in its off mode.
Pull the trigger and let water and air pass through it.
This process can move air through the tube and trigger to get rid of clogs.
You can prevent clogs by cleaning the nozzle with vinegar and a needle.
6. Blown Fuse
The final reason your electric pressure washer won’t start even if the water is on is due to a blown fuse.
Older pressure washers wear down over time.
If one of its fuses blows or becomes damaged, then the engine won’t start.
Fix: Replace The Fuse
All you need to do to fix the problem is replace the fuse.
Consult the pressure washer’s manual to buy the right kind of fuse for your washer.
With a new fuse installed, the engine can start.
There are a lot of reasons your gas-powered or electric-powered pressure washer won’t start.
Water doesn’t always matter.
Look for the problems above and use their respective fixes to get your pressure washer running again.