What is the largest GPM pump I could upgrade to with a Honda gx 390? It currently has a 4 gpm 4200 psi belt driven.
Probably 100 gpm if you turned it into a trash pump. For pressure washing the formula is
GPM x psi / 1100 equals hp
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I’m old, tired and lying in a motel bed lol. Check my edit
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You can gain either pressure or GPM with that motor, but not both. It go for gpm
That was my plan. I was hoping to get an 6 or 8 gpm pump.
8 gpm would put you around 1600 psi, minus about 300 for hose length. Fine for washing siding but couldn’t run a surface cleaner with it
That really depends on how much money you want to spend. You could run a cat 650 7gpm at 3000 psi with no problem. What are you washing would be my first question?
You could…but you definitely wouldn’t get 7gpm at 3000psi
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Cat says you will get that with 18hp at 1000 rpm you just gotta be willing to pay for it
A gx 390 is 11,12 hp.
You are correct I’m sorry I read that and immediately was thinking 630 sorry. I should stick to drinking and reading not drinking and commenting
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Awe heck man. It’s good ,it’s just brain storming ,ain’t like you pinky sweared on you’re life or nothing. …@Firefighter4hire
Lol. I don’t drink and I miss read stuff often
Many have put a 8gpm pump on the gx390 and strictly used it for house washing like IBS mentioned. If you want to use it for driveways as well you’ll have to go with a 5.6gpm pump which will put you at 2200-2400psi depending on hose length. This works for concrete but you’ll have to use a bit stronger post-treat on it.
@Barry1 Thanks for the info. I guess I’ll just stick with the 4 gpm until I have enough to upgrade the whole unit.
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Liar. We all know you Canucks drink Maple Syrup like it’s going out of style.
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Nothing like a cooling off with a bottle of maple syrup after a hard day’s work
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LOL “cooling off”
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