New belt driven pump for Honda gx390?

My 5.5 gear drive does great (and even 2000 psi is plenty).Please don’t forget, you are SUPPOSED to run small engines wide open all the time. Not doing so is bad for them. Poor maintenance would be a much larger concern, so stay on top of it.

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Bingo. Especially if you’re not forcing stuff off. Forcing stuff off = damage.

Yes, that is true. I guess the school of thought is that it’s easier on the engine to not run it at 100% LOAD.

A 13HP engine driving a pump that requires 13HP to run has a 100% load. But a 16HP pushing that same pump is only running at about 80% load, even though it’s still at max RPM.

My personal theory is that these small motors, especially Hondas, don’t really mind running at 100% load. And besides, if you’re down-streaming/softwashing with it, the only time the motor experiences a full load is during the split second it takes for the unloader to kick into bypass.

Yeah I’m trying to figure out what pump they use. Buisness is at a stand still right now since my power washer is down. Pretty sure I’m taking this first year as a HUGE learning experience. There is so many things I want to do different for next year. I really learned what matters vs things I want to do.

Are gear driven still good pumps? Everywhere I hear is go with belt drivin. And do you know what pump it is that’s 5.5 2500 psi? I found the eagle series power washer on a website but they didn’t have the pump description (at least I couldn’t find it)

This is what you are looking. Probably find it cheaper elsewhere. I’d try a gear drive now. Years ago they weren’t reliable. Gear and polychain are as good as belt drive now I believe.

https://www.jnequipment.com/shop/brands/general-pump/general-ts2021-slap-happy-fully-plumbed-pump-5-6-gpm-3500-psi-2/

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Here’s one link for the Udor gear driven pump you’d want. May find a better deal elsewhere.

http://www.powerwashstore.com/P/1886/UdorGearReductionDrive5.5GPM-4000PSIPumpNoGKC21-28-GR

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Bingo. That’s what i was looking for for him

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Isn’t that way too much psi for the Honda gx390? I was thinking I needed the 2500 psi (5.5gpm) correct me if I’m wrong thanks u

Is gear drive the same as direct drive?

No…

That’s the max PSI of the pump. Using larger tips (7.0) and setting the unloader lower makes it a lower PSI machine.

But yeah, if you tried to use 5.5 tips and kept the unloader at the max pressure, the gx390 would definitely stall.

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I think those pumps can fit on engines with more HP than a GX390, so it might be capable of 4000 PSI on another engine, but with a GX390 it will top out around 2500. Something like that.

Gear drive is better than direct drive. Direct drive, the crankshaft goes straight into the pump to turn it at the same speed… gear drive the crankshaft turns gears, which then work the pump at a different speed than the crankshaft is turning. Something like that. I think it’s better for the pump to be gear driven, and it pulls water from a buffer tank better. …something like that.

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Awesome thank you so I can run a buffer tank on just gravity like a belt drivin correct?

Sorry man kinda a noob I only thought there was direct drive and belt driven

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Direct drive is the only type that requires gravity feed, although i think ive seen some people here and there say that they pulled water without gravity assistance.

Gear and belt driven will pull water without needing gravity assistance.

Meaning: If you have a gear or belt driven, you dont need to have the tank higher than the engine to pull water.

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Am I correct in my thinking though that if a gear reduced pumps still rotates faster than a belt driven pump? Is one more efficient at pulling water than the other?

I thought I read that the slower the pump turns the better suited for pulling water.

That’s makes sense from a suction standpoint.

I think i recall seeing a lot of people stating that belt driven rotates slower than gear drive… however, i wanted to make sure about what i was saying before i repeated that here, so I did a little searching. Here’s a thread where several people discuss this issue. Skimmed through it, but if i am interpreting it right, Jerry and Russ (Two guys that know what they are talking about) say that belt and gear turn at the same RPM. There was one guy that disagreed… but it seems he might have been wrong, based on the conversation.

So it might be true that a slower turning pump pulls water better, but according to Russ and Jerry, belt driven and gear driven turn at (or near) the same RPM… so they will perform equally.

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Jerry McMillen’s posts on that thread were spot on.

My summary/takeaway:

Gear boxes are typically 2.1:1 reduction. So they require a different spec’d pump (1,750 rpm) than a typical belt drive (1,450 rpm). You could use a standard belt drive pump on a gear box, if you reduced the engine rpm. But that’s just silly. And likewise, if you had a gear reduction pump sitting around, you could find the right pulleys to install it as a belt drive.

1,750 rpm is still way better than the 3,600 rpm a direct drive turns, and it will have no problem pulling from a tank.

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