13hp honda with a 8gpm 1750psi pump


heres a dumb question(s) for you as I am very mechanically challenged… I have a 4gpm 4200psi honda gx390. The pump it came with is garbage and will soon crap out on me. However I know that the honda engine is pretty good so I would just like to upgrade the pump to an udor or some other high quality pump. My questions are:

-Does direct drive/belt driven have to do with the engine, pump, or both? If I have direct drive could I make it belt driven with a pump or is that all on the engine?

  • My assumptions are that the GPM and PSI are dictated by the pump that I buy as long as it is compatible with my GX390 correct?

-Im also assuming that a GX390 would be able to handle a 5.5GPM pump but probably not a 8gpm ?


I’ve had it pretty good in life(so far)…Maybe a few months with the 4GPM is what I need!haha. And I like the idea of having it on the trailer also with the 8GPM soon…then at least I can put my nephew to work on driveways while I house wash!


Oh for sure I do. I just like being able to move fast now with the 8. I run a big guy or my WWC with either a 4 bar or 2 big tips. And I’m about to order my 3 set of damn lights. First set worked for about 4 months then started smoking and fried the relay box. The set currently in there just quit working the other day. Once again the box is the issue. Some kind of short in it. So I’ve figured out what the weak link is. But for $35 I can’t do without them lol. I’m gonna look for a better set I guess.


Man…I hope you get it fixed. I’d like to do it on the flat bed, but not if it’s gonna burn it down. Lol it’s already mechanically “questionable”


Do search on that. An engine is an engine and can be converted to a gear drive/belt drive pretty simply.


Yea i doubt I can fix it. Just going to order another kit. It’s weird though. This time I actually took the time to shrink wrap the connections and put dielectric grease on all the connections thinking that would make it last a long time. Apparently not. Could be completely coincidental though and I just got a bad box.


My box smoked out as well. I put the new one in a plastic bad…its working so far


Ps thanks again for the awsome idea


That’s pretty rad


Wish I could take credit for it… that’s all @Alabama idea.
“We like clean houses and we cannot lie!”
Still the best thing ever!


Lol. Yea I’m gonna definitely seal the next box when it comes in. Definitely looks badass. I like the slow fade. I keep them on riding down the road. Looks like a space ship at night.


Ok Ive been crunching numbers…Thinking I can pull off the Honda 8GPM GX690 3000PSI. Its not the 3500psi…But Im thinking that the 8GPM will take care of my residential surfacing cleaning worries that the 5.5 2500 was giving me.


3000 PSI is perfect for nearly everything you’ll ever do. You’ll never say… man… I wish I had gone down in GPM for more pressure. Lol. If you ever feel that way deep in your soul I’ll send you 500 PSIs.

(I don’t know how to send you PSIs… so you’ll have to settle for pizza or something.)


Haha. Pizza and beer it is! Now I move my focus to the damn size of tank I need now…was gonna go with 65 gal…but thats got to be out the door now…5X8 trailer single axle. Ugh


Referring to space limitations or weight limitations?


65 is perfect. What’s wrong with 65? I carry a 275 on a single axle 6x10.

@Innocentbystander runs two 8 gpm machines off a 65 gallon tank as I understand it. Do I have that right Will?


I said 690 before its the 630. Anyway…just thought I would have to be showing up with more water pushing the 8GPM now. But as Im doing more “searching” I see that it will work out for me. Was kind of worried about weight a bit…Have a 15’ grand cherokee with the 300hp V6…knew I shouldnt have sold my truck!ah. Thanks for the responses fellas.


More weight


Tank empty is light


Keep the machine near the tongue (or 15% of the total trailer weight near the tongue and only travel with 20 gallons of water. Run hoses first thing when you get the job and let it start to fill while you tape things off, get your pressure hoses run, etc.