# Pressure washer makes loud backfire noise



## Housepaintersottawa

Hi Guys,

Just bought a pressure washer and after turn the off switch it make multiple loud backfiring noise for at least a minute till it finally stops.

Anyone know the reasons for this?


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## Ultimate

It's still burning fuel. No biggie really. 

What washer do you have?


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## PressurePros

I'm guessing the engine is a Honda? It's common and it happens with other motors, but almost every Honda I have owned has done that at one time or another. 

Edit: Just reread your post. If that happens multiple times for a full minute, that engine has something wrong with it. 

Is it post ignition detonation (sounds like the engine keeps chugging and strugglling after you turn the key off) or full on backfires (like a gunshot)? Neither are good if you are certain about it being a minute.


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## PressurePros

I usually get one loud bang that can make you crap your pants and leave your ears ringing. One way to avoid it is to lower your throttle down before shutting off the engine.


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## PRC

PressurePros said:


> I usually get one loud bang that can make you crap your pants and leave your ears ringing. One way to avoid it is to lower your throttle down before shutting off the engine.


Throttling down is best for most small engines. Too many full throttle shutdowns and you risk valve damage.


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## driftweed

Mine did that when i first purchased it. I was putiing in mixed fuel. Then someone pointed out it took straight gas. Problem solved. Oops!


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## stelzerpaintinginc.

If the washer is backfiring after you shut it off, then it's technically called, "Afterfire", in which case throttling down 10-20 seconds before shutoff can help. 

If the engine is backfiring while running, it can be for various reasons, most commonly due to:
-lowering throttle speed too fast. 
-carburetor running too lean. 
-too much alcohol in fuel
-engine running too hot.


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## Housepaintersottawa

This thing is suppose to have an auto throttle. Second time using it.

Its a Stratton and Briggs 2600psi. 2.3gpm


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## Ultimate

Did you try idling it down first before shutting it off?

How old is the gas?


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## Nabinko

It should not be backfiring. What is the model number on the actual Briggs motor itself? Is there just a regular screw/bolt holding the carb bowl in or is there a fuel solenoid? If you can't exchange it for a new one try these 2 suggestions to start:

- Add an inline fuel shut-off valve. * Cut the fuel off and let it run for a bit before shutting down the ignition.

- Check your valve clearances and adjust if needed.


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## GHP

I have Champion 3200 psi washer. First time I used it, I shut it down, it after fired on me scared the living lights out of me..It happens every once in a while...more less than often.


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