Tank below machine question?


I’m building a skid right now in my truck. I have a 200 gallon low profile tank that fits under the skid. The machine will be mounted on the skid above the tank. I plan on using my 12v pump to pull the air out of the system each time I need to prime.

My question is will it harm my machine to mount it above the tank? Will it cause cavitation?

8.5 gpm general pump gear drive and 23hp engine.

The whole point of this skid setup is so we don’t have to pull a trailer (mainly so my wife can wash by herself while I’m at work)


You’ll be fine. Mine is about 3’ above my tank outlet. It’s a belt drive but your gear drive should pull it just fine. Don’t worry about priming it with the 12volt. Just watch it when you start it up (and not wide open on start up) and make sure valve open on your output line and it should be pulling water in just a couple of seconds.


That’s a big relief! Thank you sir!


I’d like to see your setup when you’re finished. Very interested.


What size truck will you be putting all of this in?
I ask because just with the 200 gallon tank alone when its filled you could be looking at + - 1700lbs.
Add on a chem tank, hose reel, 8gpm machine, and your looking at some serious weight even for a 3/4 ton series truck.


Its a F150 but I sure push her limits Here we have 50 50LB salt bags weighing in at 2,500LBS with a 175LB salt spreader and 1,900LB plow. Add my 312 LB A$$ and we are pushing the limits. We run 12 ply tires at 80PSI

I will not be hauling water in this truck. (maybe occasionally but not likely)


I’m working on it every spare second I have. Darn daytime job takes up all my time. But at least I can get on here and read PW stuff half the day lol.

The plan is as followed.

35 gallon SH tank against the headache rack
8 gallon soap tank against headache rack
200 gallon buffer fits under the skid leaving me about 9 inches between it and tailgate for plumbing.

Both will be piped to the back where when I open the tailgate I can sit my mix backpack sprayer down under the valve and turn it on to fill it. This should make it where I wont spill a drop.

Backpack will hook to my Xjet

I have a 12v pump that I will be hooking up so I can do a few things with it. I can pull SH from the pool store barrels and transfer it right back into my tank (no lifting and spilling) and do the same with the soap.

12v will also be able to pull out of the buffer for rinsing or emergency eyewash.

2 450ft hose reels mounted on passenger side facing curb
1 will be for 1/2 inch PW line
1 will be for buffer tank feed

Trying to get it all together soon as we have about 25 homes lined up ATM and a golf course that wants EVERYTHING cleaned. Still gets too cold here to start for the season.


I’m curious as to why you’re using 1/2" pressure hose instead of 3/8"? It’s my understanding that it is much heavier and cumbersome. And 450’ sounds like a long lay.
You could downstream right from your tanks and use a proportioner so you didn’t need the backpack tank, just use a M5DS nozzle if you want it to be adjustable. Feel like filling up that backpack a few times per job wastes alot of time.


1/2 will be because of flat work at 8.5gpm I will loose 300 PSI per hundred foot with 3/8 and only loose 80PSI per 100 at 1/2

I have considered DS But I like having that instant on/ off control of the x jet.

I would only be refilling the backpack if I was doing a really large house. I usually only used 4-5 gallons of SH per wash.

I’m open to trying both. Maybe DS large homes and XJET average or smaller.

Why I don’t like DS because in the past we would be rinsing and see an area that is still being stubborn. I could either
A: install a remote soap switch
B: walk back and turn on the soap

Do you really get a good mix when you DS? I am going from a true softwash with 12v to xjet. I have only ever DS SH a few times and was not happy with the results of how lean the mix was

Will I even be able to DS with 300ft of hose? Will it pull a good mixture?


I saw it on your video.
But i also saw a blue filter, i assumed it was for the 8gpm machine. I tried it feeding mine with it and couldnt.
Now i got a banjo 2’ strainer with a 1.5" barb.


I think friction loss is only 100 psi per 100’ of 3/8" hose. I could be wrong.
I have had no problems DS. I have a pump up sprayer with a more concentrated mix for stubborn areas. Not knocking how you do things, just thinking aloud. I think some injectors will pull up to 300’. Otherwise you could move the injector up the line for a long hose lay, have it at, say, the 200’ mark or whatever.




Awesome. Thanks!


Not sure how you had hooked up. I’ve had no trouble with either of mine and I know plenty of others who use.


How I had the buffer tank hooked up or my line size? Do you run an 8GPM machine with 3/8?


I had the blue filter hooked to 1" hose and to my 8gpm and it wasnt supplying enough water.
So i replaced it with a 2" banjo strainer.


1" line will easily pull 22gpm. Must have a heck of a pump on it.:sunglasses:


Honestly no idea what i did wrong, had to hook the pump directly to 1" hose to work.
Since i had a job last weekend.
I have a filter going into the tote and each feeding line to the other machines have their own filter too


What gauge/ size tubing are you using for the skid frame?
Is that painted plywood? Or composite “plywood”?
I plan on starting a similar project soon, with a smaller belt drive machine.


Sorry thought i was being asked