Pressure won't release once started

Hello so I have a pressure washer that won’t release pressure once it starts. At first I thought that the air is stuck in the hose that is causing the issue so I hold open the gun and then start the engine. The pressure washer works fine as long as I don’t let go off the gun. As soon as I let go, its not able to release pressure and you can feel the pressure built up in the hose. The only way I can then release pressure is if I take out the pressure relief valve. Can you shed some light onto what might be wrong with it?

Does it stall the engine?

No it doesn’t. The engine keeps running. One thing I did noticed that my thermal relief valve is always letting out water after connecting the water hose. I thought it was unusual as it is leaking water even when the machine is not on.

Is there an unloader?

There is an unloader valve.

No it doesn’t. The engine keeps running. One thing I did noticed that my thermal relief valve is always letting out water after connecting the water hose. I thought it was unusual as it is leaking water even when the machine is not on.

Unloader stuck.

if thermal release valve is leaking bad enough the unloader might not kick over. A bad leak isn’t much different than pulling the trigger on your gun. If that’s not it I agree with Hotshot. It’s definitely the unloader.

I took the valve out and checked if the valve pin was stuck. It wasn’t looked fine to me.

Just plug the thermal relief valve hole for now to troubleshoot. You have to stop the leak before you do anything else. If you’re still having issues after stopping the leak rebuild or buy a new unloader.

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New unloader, $48

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And does it bypass at all?

Hate to say it but sounds like your washer is operating normally. Unloader could use a bit of adjustment maybe along with replacing the thermal relief valve.

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