I did say "is someone were to run it with no flow through the pump".
The big commercial ones have a bypass that keeps water flowing through the pump. I know the little cheap ones don't have this.
Pressure washer dumpster find
- Thread starter 92saturnsl2
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The big commercial ones have a bypass that keeps water flowing through the pump. I know the little cheap ones don't have this.
That is what I was referring to. The water circulates from the bypass back to inlet. Round and round getting hotter and hotter, eventually it will melt nylon parts.
Some commercial setup with a big water tank on a trailer route the bypass into the tank. So no really chance for the water to get hot. But without a tank you need to get careful.
I own the big brother to that unit with the GX270 engine. It's a Simpson-made unit.
Like most such PWs, it uses a real Honda engine for marketing and pairs it with a trash pump AAA pump. I think my pump lasted all of maybe 50 hours.
I replaced it with a CAT 66DX 4.0 GPM pump. Normally you'd think a 4 GPM pump is a bit too large for a 270cc Honda (they typically would be paired with a GX390), but looking at the pump curve against the engine curve, I was convinced I could run the larger pump if I correctly sized the orifices down to run lower pressure.
It worked like a charm. The factory AAA pump was using 3.5 orifices for the advertised 3.5gpm. Which of course means it's trying to push nearly 4000psi.
WIth my 4.0 GPM pump, I'm running orifices from 4.5 to 5.5 to get pressures from ~3000 to ~2200psi respectively. And it works SO much better having gobs more flow at lower pressure.
Plus the lower pressure take a lot of load off the pump compared to running near its max rated pressure. This is less pump heat.
More little GX270 is running it like a champ. Yes, if I put in an undersized orifice, I can lug that engine down to near rated torque and get both lower flow AND lower pressure than a "correctly" sized pump.
My setup is now engine-limited instead of pump-limited. That GX270 gets VR1 synthetic 20w50 and is happy as a clam to run as hot as I can get it.
Yes to 20w50 in the engine, but don't run gear oil in the pump if it calls for motor oil. The EP add pack in gear oil can eat some kinds of seals or even the pump body. If it says engine oil, use engine oil.
Oh I've never had a problem using gear oil. Longest I've had gear oil in a pump was about 7 years and then someone stole it.
Those DeWalts were built by Simpson. Have one, also had to change pump.
https://simpsoncleaning.com/
https://simpsoncleaning.com/
Good to know, sad that they use those crap AAA pumps. I'm going to take it apart for science, I bet it's full of plastic parts.
I finally found the appropriate fitting to convert new pump quick connect to what I now know is an M22 fitting w/ 14mm bore (standard residential pressure washer hose fitting). I'm about to try it out momentarily, will report back.
I installed a pop off valve for pressure spikes. Also a thermal overload valve as well for if I walked away too long. I did not want to blow my pump like my brother did. Adds cost and labor/w fittings, but makes for piece of mind.
Turbo nozzles work awesome for certain weeds. I blasted a bunch of moss, smaller ferns, and some weeds amongst some rock areas I have. Rocks were some bigger ones, and smaller 2-4 inch sized ones.
I also used the turbo nozzle years back with tree debris that had been left in the grass too long. The grass started growing over the branches like vines. I used the turbo nozzles to blast the grass so I could pull the sticks and such off the lawn. It was a huge help.
Turbo nozzles work awesome for certain weeds. I blasted a bunch of moss, smaller ferns, and some weeds amongst some rock areas I have. Rocks were some bigger ones, and smaller 2-4 inch sized ones.
I also used the turbo nozzle years back with tree debris that had been left in the grass too long. The grass started growing over the branches like vines. I used the turbo nozzles to blast the grass so I could pull the sticks and such off the lawn. It was a huge help.
With the new pump, this is a mean machine.
I have a lot of square footage to cover, completely refinishing our wraparound deck and balcony. Strip as much paint as I can, clean everything good and repaint. I'm replacing any suspect wood while I'm there. I found the spinning jet nozzle to be the best for the job, but I'll use a 45* nozzle for cleanup going top to bottom before final stain/paint.
By the time I'm done I'll be approaching the first oil change for the pump. The manual has me scratching my head though-- it suggests 10w-30 or 15w-40 non detergent but I'm not sure that exists. It gives some API classifications but those would have detergents in them.
Only thing available locally would be 15w-40 HDEO, 10w-30 motor oil, or non detergent SAE40 oil. What would you folks recommend for the pump oil?
I have a lot of square footage to cover, completely refinishing our wraparound deck and balcony. Strip as much paint as I can, clean everything good and repaint. I'm replacing any suspect wood while I'm there. I found the spinning jet nozzle to be the best for the job, but I'll use a 45* nozzle for cleanup going top to bottom before final stain/paint.
By the time I'm done I'll be approaching the first oil change for the pump. The manual has me scratching my head though-- it suggests 10w-30 or 15w-40 non detergent but I'm not sure that exists. It gives some API classifications but those would have detergents in them.
Only thing available locally would be 15w-40 HDEO, 10w-30 motor oil, or non detergent SAE40 oil. What would you folks recommend for the pump oil?
