15-Gallon Spot Sprayer – 1.0GPM, 40PSI Max

There is ONE manufacturer who makes ALL of these tanks, regardless of their size.The tank itself is perfect, as it is good material that will last a long time.The only difference between this sub-$100 sprayer and any sprayer costing any more (up to $500) is just how crappy and cheap a pump is on any of them. I knew that no 1.1gpm pump is going to be satisfactory for spraying stuff up to 20′ away. High pressure without high volume just creates a wide mist or a short weak stream. Not even the $500 ones have a great pump on them.IT ISN’T PSI THAT MATTERS, what matters is GPM!So I looked for the cheapest model and ‘brand’ of sprayer available in the tank capacity I needed and bought it. Then I went looking for a pump that would actually work. The pump I chose is attached to the tank and the original weakling is sitting beside it for comparison.The biggest complaint about the el cheapo pumps is that they lock up after minimal use, followed by “pump leaks” in close second place.3-chamber high-volume RV pumps don’t lock up and they don’t leak.They also have the same to slightly better PSI rating but they deliver AT LEAST 3X the GPM.In other words, to get the same plant just as wet, you have to hold spray on that plant 3X as long with a 1.1gpm pump. Or in other worss, you get done spraying 3X as fast with the pump I put on mine. I ordered both pump and sprayer from Amazon.I took the original pump off, welded up a ‘motor mount’ plate made from a junction box cover and a meter base knockout cover, welded some threaded studs onto the mount in the right places, and voila! great pump in place of crap!I had to modify the suction hose but that was Just a matter of a brass PEX elbow and 2 stainless steel screw clamps in place of the el cheapo plastic squeeze-fit clamp.Another complaint I headed off at the pass was the “it leaks by the vent hole/lanyard point in the lid when liquid sloshes around while moving” gripe. Well, liquid tanks NEED vents. So on the underside of the lid you find the vent hole, but it isn’t flat across the bottom, it does have a 1″ dia by 1-1/4″ long ‘baffle,’ a funnel really that makes the liauid have to work a little harder to get out the hole. It isn’t enough baffling, so I got a Scotch-Brite green scouring pad and cut three discs the size of the vent funnel out of it and stacked them inside the vent hole funnel. A dab of silicone sealant on the edge keeps them in place. I used Scotch-Brite because it is pneumatically transparent but will not get stopped up when wet like a cotton ball or rust out like steel wool. The lid and the tank are not made of the same material so the tank leaks THERE too. I got a sheet of cork gasket material at the parts store, cut a gasket for the lid out of it, and glued it to the lid.The absolute best way to prevent liquid from sloshing out of any tank is to build-in baffles in the tank which make the liquid change directions several times before it can get out. China didn’t and after it’s made, you can’t so you have to make it harder to get out. Just understand that this is basically farm equipment and not a Cuisinart in your kitchen, and that some liquid is just going to escape the tank.I retained the in-tank strainer on the hose. This will keep insects from getting sucked into the filter jar on the pump. The main problem causing lockups on the original pump is that the ONLY liquid filtering happens in the tank and the strainer holes let particles big enough to Cut, puncture, or otherwise damage the tiny original weak pump’s diaphragm. The big pump I installed came with a MUCH better filter that is OUTSIDE the tank consisting of a screw-off clear sediment trap and a much finer filter screen. It can be cleaned without sticking your arm up to the elbow in a tank full of poison. This bigger pump will therefore ONLY get liquid inside it. Any large trash that gets by the in-tank strainer will not get by this filter jar. The original pump would be able to get particles larger than salt crystals in it, because the pores on the hose strainer in the tank are larger than salt crystals. A diaphragm pump MUST have fine-particle filtration or the very thin diaphragm will be cut or punctured and then non-wettable parts get wet, and the motor locks up. This isn’t rocket science, it’s cheap Chinese manufacturing.It took me a couple days to get everything to line up right, manufactured, painted with Rustoleum and cured with sunlight before installing the whole shebang on the tank.I am now welding up the trailer I’m building for it so I can power and tow it with my golf cart.I will update this review after initial use, and then again after 90 days.I will add pictures of the fully-completed assembly along with a frank performance review in a matter of days.It all condenses to this: for under $175, I now have a sprayer that is the equal of any sprayer costing up to $1,000.You just have to have brains and know which end of a screwdriver to hold and you can too. [...]