A big thanks

Long time lurker here for personal projects.
As someone who started snooping around a couple years back I feel I have gained quiet a bit of information from doing a lot of reading here. Thanks to all for sharing your expertise. This place is like a virtual encyclopedia.

Heres a little rig I put together. Nothing fancy but I’m in it for about $2000 total with a new pump. Used alkota skid I picked up for $500 from a guy who was in over his head trying to fix the wiring.
Honda GX390
CAT 5CP3120 4.5gpm/3500#

Just breaking out but hoping this will be a decent little residential/light commercial money maker. Far from perfect but hope to tune it up going forward. Have since wires in an adjustable thermostat as well as picked up a 20” floater.



What are the metal jerry cans for? Not bleach I hope.

No sir! Just extra fuel. Last thing im going to do is stop and drag up over fuel. I have a 35gallon chem tank on the back side and a couple job boxes back there as well for the miscellaneous pump ups, chem jugs, tools, etc Kinda a bad picture i guess.

Just got one big gas can instead, you’ll be able to fill your tank almost a handful of times with it and you’ll save the room that you’ll soon need. You’ll run out of room sooner than you think lol. Best of luck out there.

How old is that motor? That GX390 has to be at least 15 years old judging by the key module and front cover, my first machines looked similar, goes to show the reliability of the hondas, probably original internals as well and still kicking. Chuck those gas cans to the back of the trailer, those steel cans would be like bombs going off next to that exhaust.

I appreciate the input fellas. The steelies weren’t my best idea in all honesty and the couple comments I’ve got on them just confirm my reservations that I had. I run a 60 gallon aux tank for diesel in the bed so in all honesty those things are just taking up space. A couple VP jugs of gas will run that thing all day. Struck a deal on a GX 660 for 500 bux with 300 hrs on it so Im going to repower with that and run another poly tank since they have fuel pumps vs the limited capacity on the 390. The 390 is a tad underpowered for the pump I feel honestly plus no external filters etc.
Hoping the trade off of hot water for tad undersized unit will pay off.

Im thinking 10-15 years without checking the serial. Honestly with the exception of being left in the sun and faded that little motor cranks right up. I guess thats why I run honda gensets/small motors on anything I can. Quality costs $.

Keep in mind that a Honda 630 or 690 is going to have a larger crankshaft diameter so you’ll also need to get a different pulley.

That GX 390 should be fine for a 4.5 gpm pump. You might not quite get the 3500 psi but that’s okay. There are guys on here that run 5.5 gpm pumps on a 390. I think you’re better off picking up an 8 gpm pump and slapping it on that 690. You’ll then have plenty of gpm for most jobs and also hot water when needed. You’ll have the best of both worlds plus a backup machine which can save your day.

If interested there’s a way for you to get pulse off of that 390 to where you can run a fuel pump. You could then disconnect the fuel line from the original tank and get a larger remote tank.

Yes I’m the pulse. I haven’t tried it yet, but my research shows use the carb spacer with the nipple on it is best. The other way using the blvd cover is involved and can get oil in carb.

Yep, both ways seem to work equally as good. I put an 18 hp engine in our golf cart and added a barb to the carb spacer to get a pulse. I’ve also drilled holes in valve covers and added a hose barb. I’ve never had an issue of oil being pulled through. I imagine it could happen if you placed the barb near the bottom of the valve cover or in an area where oil kind of collects before it drains back down to the crankcase. If it does ever happen you could always fab up a little shield that blocks the hole a little.

You can also place a barb near the top of the crankcase to get pulse but I’ve never tried it. I never wanted to drill a hole in the crankcase because once it’s there it’s there. At least with the valve cover you can replace it for $5-$10 if you ever wanted to do away with it. I would think the crankcase would have the biggest chance of oil being pulled into the hose since oil is splashing all around.

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