Skip to Content

Pressure Washer Won’t Start After Running Out Of Gas – Try this

By: Author John Cunningham. Published: 2021/07/05 at 9:54 am

Running out of gas is a common occurrence; in my workshop, I hear customers describe this exact issue a lot. You are in the right place; a few minutes from now, you’ll be back washing.

A power washer that won’t start after running out of gas likely suffers from an air-locked fuel system or dirt in the carburetor. Draining the gas bowl very often fixes the issue.  

In this post, you’ll learn why your washer won’t start after running out of gas; you’ll also learn how to drain the gas bowl and how to clean the bowl.

Air Locked Fuel System

While an air-locked fuel system isn’t hugely common it can happen when a pressure washer runs out of gas. Air locking occurs when, as its name suggests, a bubble of air prevents gas from making its way to the carburetor.

The bubble of trapped air usually happens inside the small gas line between the gas tank and the carburetor. 

Partially filling the gas tank after running out of gas will increase the chances of air locking. It’s best to fill a gas tank as the weight of the volume of gas helps push trapped air to the carburetor, where it’s expelled.

Removing The Air Lock

The fix is simple, follow these steps:

Gas – Fill the gas tank and leave the gas cap off

Remove gas cap
Tapping on carb bowl

Tap – Tap on Gas Bowl

Give it a minute or so before attempting to start the engine.

For most, this simple procedure is all that’s required to remove the trapped air. If, however, that isn’t the case, draining the gas bowl will release the air. I cover that exact procedure below in gas bowl cleaning.

Dirty Power Washer Carburetor

Carburetors are finely tuned components that are tasked with supplying your power washer engine with the optimum volume of gas for the engine load. It manages this process precisely by employing small passageways and ports in which gas flows. Even a tiny blockage is enough to cause a no-start.

Dirt enters the fuel system, usually at refueling, small particles of grit eventually make their way to the carburetor. The gas bowl is a fuel reservoir at the base of the carburetor. Any dirt in the fuel system will collect in the gas bowl. The bowl also houses the gas feed, which may be called an emulsion tube or jet. It’s a siphon that feeds gas to the engine.

It’s easy to imagine how a grit particle could block the siphon process. 

Next, we’ll look at how we can remove the dirt the easy way.

Diagnosis & Repair

In many cases, draining the gas bowl is enough to release the dirt. However, bowl removal may also be required, and if that doesn’t fix the issue, we’ll need to remove, strip, clean, and refit the carburetor. But hey, let’s think positive; let’s just try draining the gas bowl first and see how that goes. 

Draining Carburetor Gas Bowl

Here, we’ll drain the gas bowl and test start the engine. The tools you’ll need include a wrench set and some old cloth. As we’ll be working with raw gas, it’s best to work outdoors, away from sources of ignition. You’ll also need gloves and eye protection.

Note: Not all gas bowls have a drain bolt, so if yours hasn’t, go ahead and see the cleaning gas bowl below.

Follow these steps to drain the carburetor gas bowl:

Snow blower Gas off

Gas Off – Turn the gas tap off

Locate – Locate the carburetor bowl drain bolt (if fitted)

Bowl bolt
Bowl drain

Drain – Remove the drain bolt (place cloths to catch the spill) and allow the bowl to drain.

Rinse – Turn the gas on momentarily to rinse fresh gas through the bowl.

Now refit the drain bolt.

Bowl drain

If that worked out for you, fantastic! If it didn’t, we’d need to move to DEFCON 2 – cleaning the gas bowl. See below.

Cleaning Carburetor Gas Bowl

Some tools, safety kit, and precautions are needed here as they were in bowl draining. In addition, a can of carburetor cleaner would be useful. You’ll find all the tools to nail this repair here on the “Pressure washer maintenance tools page.”

Note: Old gas bowl seals often leak after being disturbed; if your bowl develops a leak after refitting the bowl, go ahead and replace the gas bowl seal and fastener gasket.

Remove and clean the gas bowl as follows:

  • Turn gas off
  • Place cloths under the gas bowl
  • Remove the bowl fastener
Fit gas bowl snow blower

Remove – Remove bowl fastener

Clean – Some power washer carburetors may employ a carb bowl bolt jet combo. You can identify it by its portholes.

These holes must be clean; often, with this type of carburetor, that’s all that’s needed.

Bowl corrosion

Check – Rusty bowl means the carb needs to be replaced. Otherwise, go ahead and clean the bowl.

Carb Cleaner – Use the carburetor cleaner straw to spray the jet/emulsion tube.

Carb cleaning
Fit bowl

Refit – Refit the bowl taking care to seat the gasket correctly.

For the great majority, I’d expect this has nailed the problem; however, if you’re still not power washing, we’ll need to remove and clean the carburetor.

Clean The Carburetor

All carburetors need to be cleaned; you will notice the difference afterward. Some carburetors are easier to work on than others; power washers tend to be pretty easy, though. 

Spray carburetor with cleaner

Carb cleaning

As this is a common issue, I covered it previously in this post, “Lawn mower carburetor cleaning.” The post covers a mower carburetor; the process is identical, and all these engines are very similar.

Or check out the videos on this page – “Carburetor cleaning videos.”

For parts and tools, check out “Power washer maintenance tools.”

You may also find “Pressure washer troubleshooting page” useful.

Other posts you may find helpful:

Power washer hard to pull

Power washer oil level check