Unknown Chinese pump pressure testing?

Hi guys,

I have an unknown Chinese pump. From what I have found online, I believe it MIGHT be a 4 GPM / 2000 psi pump. It has a built in unloader

Now, when using 4.0 orifice nozzles with white tip, the pump will put out over 2000 PSI, like 2500. Is this normal? I don’t even have the unloader maxed out. I mean surely they wouldn’t put an adjustable unloader on the top of the pump that you can adjust (giving the normal population who don’t know anything about pumps a chance to adjust things) and make it so you can explode/internally damage the pump?

Also I’ve tried running smaller size nozzles on it because I wasn’t sure of the size before, and it will put out 3000 psi no problem (of course less water flow). Same unloader setting.

Any guidance here? Obviously I don’t want to blow the pump up, but at the same time I would like to find out the proper pressure to run it at.

So many things.

Unloader should be set properly and never touched again. (Search bar: adjust unloader) Yes, they make all kinds of machines that people can buy, use improperly, and hurt themselves with.

Get a pressure gauge and set it properly, then use the correct size tips to lower your pressure for what you’re cleaning. Under 3k psi for concrete, 1k for wood rinse, under 100 for vinyl

Right. Just you see the regular pressure washers that have the unloaders with handles on them, that are made to be adjusted by the customer. Maxed out setting on those is set at the factory I’m guessing so it never exceeds the pressure rating of the pump?

I have a gauge mounted directly to my pump. Numbers I quoted were pump head pressures. I want maximum pressure and flow possible for the pump. I’m cleaning mud and grease/grime off heavy equipment. But as I had mentioned before. I don’t know exactly what the specs of the pump are. There are no tags or indications on it at all. I know the ceramic coated pistons are 15mm, though. I rebuilt the pump and had to replace one of them.

Curious what makes one pump diff from another making it more capable of higher pressures? Is it the size of the pistons? Internal components? Obviously my pump can do higher pressures, but guessing it will lower its lifespan?

Pump is attached to a 13HP Honda.

If it’s Chinese it’s most likely the danau brand. Upgrade ASAP.

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Thanks but dual shaft pump, I don’t have an extra grand to throw around for a new pump because this one “might” break.

Easy Kleen machines use all Chinese pumps and I haven’t seen a single one broken…

Anyway the pump is not even a Danau…

If you do this as a job, your previous comment is so wrong. If not, use it till it breaks if you wish. Those pumps do break and they break quick… ask me how I know. EasyKleen uses them because they’re cheap. They like to slap cheap pumps on to good engines and over price them. I wouldn’t recommend them

@Sugarkryptonite is there something that fits better with exactly what you wanted to hear?

You have an awesome pump that’ll last forever.

Unloaders were meant to be cranked down as tight as you can get them; mess with it all the time.

That gx390 will give you 5000psi and a hundred gallons a minute.

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Measure the stroke and provide the piston size plus rpm and any of the pump manufacturers should be able to tell you the specs.