Someone gave me their broken Craftsman 580.752300 pressure washer 2300psi, 2.0 gpm, with 6.0 horsepower B&S 12Q802 engine.
They are saying it is a faulty water pump. Just in case, I have a whole new carburetor that I will replace as well.
I have to replace the whole water pump assembly which has the part number of 189970GS on the manual.
I am not going to purchase an OEM part as it is too expensive. So I am looking for a cheaper alternative. I found a water pump that might work. However, the vendor’s tech team does not even know if it will work.
Obviously, this item has the 7/8 shaft and the dimensions for the 3 mounting bolts matches.
This is the item: VEVOR Pressure Washer Pump, 7/8" Shaft Vertical, 3400 PSI, 2.5 GPM, Replacement Power Washer Pumps Kit, Parts Washer Pump, Compatible with Honda, Simpson, RYOBI, Briggs & Stratton, Subaru, Craftsman | VEVOR US
The question I have is this. The Craftsman pressure washer is rated for 2300 psi, but this pump is rated for 3400psi, 2.5 gpm, and for an engine with 6.5 to 7 HP. This pump seem a bit “overpowered.” Would this work on the Craftsman pressure washer?
GPM X PSI / 1450 X 1.5 = HP needed
You would need at least 9HP to run that pump for what its rated. Will 6HP still work? Yes, you just aren’t going to get the rated PSI.
When you mean I am not going to get the rated PSI, are you referring to the 2300 PSI or the water pump’s rated PSI of 3000+ PSI? I am satisfied if I get 2300 PSI out of this?
Second follow up question, will this damage my engine because it is trying to run 100% all the time?
You will not get the 3400 psi that the Vevor pump is rated for. Reversing the calculation you would get 2,320 psi with that pump before friction loss etc depending on hose length.
No you will not damage the engine, it should be running 100% 3600 RPM at all times. It will only produce what it can with the HP it has.
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Great thanks. Basically I can replace it with the Vevor water pump to replace the broken OEM pump and still get the 2300 PSI which is the rated PSI of the pressure washer. That’s actually good news as I can repair the broken pressure washer for a little bit over $50.
