Back pack sprayer air intake

You can take the intake part of the pump apart and clean/lube the diaphragm of the pump. If you didn't clean it out last time it was used there will be residual or cake built up. Make sure the down snorkel is clear and doesn't have any contamination in the tube. Check the screen/filter also.

same thing happening

If sprayer doesnt seal against pressure, I suggest check cover gasket A (image 1). Check pump cylinder gasket B (image 2) and additionally, check the procedure if pump dont build pressure. on how to remoce pump cylinder on follow lines.



If pump doesnt build pressure... in most instances, failure of the pumo to build air pressure in the sprayer is due to dry or worm plunger cul leather. To work on cup leather, always remove plunger from pumo cylinder. Do not attempt to oil cup leather through breather hole in **** cap.

First, unthread pumo cap A (image 1). If cap is too tight, and if pumo will build even slight temporary pressure, pressurizing the tnak will make it easier to loosen cap. Once cap is lossened, release tank pressure. Hold pump cylinder by inserting hand through tank filler openning (image 2), and unscrew cap all the way. Pull plunger from cylinder, and remove cylinder from inside the tank.



Place a few drops of clea oil (not heavier than SAE 30) on leather, and massage into leather until it is soft. Replace plunger cup leather if damaged (image 3). to remove plunger leather assembly, use coin rather than screw driver in the slot of the plunger cup retainer. To reassemble, hold pump cylinder in tank openning, with squared edge of flange, at top of cylinder, toward tank wall.



Hope this helps to solve it.

The handle pushes down and locks to be carry or to unscrew it. Push handle down, then twist left to unscrew. It may take a bunch of force to start. Better to hold the sprayer down and relieve all pressure before doing the unscrew.

the reason it might not pressurize is there might be a hole in your tank or hose to the spraier itself if it has holes in the hose get a new one put it on the tank and handle. if hole in the tank duct tape it or seal it with a sealent. but it wont pressurize with a hole because the air comes in and out of the hole. hope this helps you

I think you need to remove the pressure cylinder. I've had the same problem with my 425 and there is a screen on the cylinder that must be cleaned. To remove the cylinder, do all the disassembly in the owners manual. Then get a short piece of 2x4 or 2x2. Place the end of the 2x4 on the pressure cylinder through the top of the tank. Give it a good whack with the hammer. It may take more than one good whack to free it, but it will come loose. Then inspect/clean the screen. You are going to have to use some force to get it back in. Turn the sprayer upside down, insert the pressure cylinder, lay the 2x4 across the bottom of the pressure cylinder and use even force to tap it back in. Stop when you get to the O ring collar and do the rest by hand being careful not to pinch the O ring. It may help to lube the O ring with vaseline.

pour about one cup of water with a dash ( tablespoon) of liquid dish washing solution onto the top of the container trying to get as much of the mixture into the handle void of the sprayer chamber. You are trying to lubricate and clean the pump. If this doesn't help the pump to build up pressure then you can look for two clips around the top where the handle and bump body are connected. If you can seperate these two parts you can see the O-ring at the bottom of the pump handle and confirm it is clean and smooth. Rub some crisco yes, crisco on it to get it lubricated and put back the plunger into the body and make sure the clips snap back together. Now turn the completed piece upside down and see the little round rubber piece? Carefully rotate it and confirm that it fits snugly onto the bottom of the assembly. Do not pull it out!! If it is old it may break. So far are you still with me?? Good! Put it back together ( putting a little crisco on the gasket between the tank and the pump assembly won't hurt here either) try to pump up the pressure. We done yet?? No? builds pressure but won't spray? Well on to the wand. Feel lucky?? Take off the wand AFTER the spray valve the thing you push to get the spray out. Try to see if the water comes out easily under the pressure you pumped up. Careful, at the very least you have the soapy water plus God know what left over in the tank as you do this. We just want to see if there is any blockage from the tank to the valve. Unless you got foreign matter into the tank of the sprayer this should not have a blockage here. You can take the valve apart but it can be a problem sometimes PLUS Remove the pressure before you do it. Work your way down to the tip to see where the blockage is. Most often it is at the tip just behind the removable cap. The cap itself can become blocked. I carefully blow out any crud. I use air from my lungs blowing from my mouth but do not recommend this method especially if posions are being used. More often it is the holes in the wand that allow the pressured spray to come out. A paper clip works great here. Bend open and clean out the holes. DO NOT use the paper clip on the cap!! you will enlarge the hole and ruin the spray pattern. If after all this you still can't get it to work properly sometimes using some of those lime away products can clean out the hardened crud.

I would say that you have a broken valve in the cylinder head, drain what pressure you have in it, with it unhooked and remove the cylinder head. there are reed type valve on a plate, the valves on the intake side open towards the cylinder and the discharge valves open towards the head. look for broken reeds or hung open with crud. also look to see if the gaskets are blown between intake and discharge side of the head, also if head gasket is intact between cylinder bores. These are the likely problems with these pumps, hope this helps!

It sounds that you need a new foot valve. It is the rubber thing on the end of the cylinder that is connected to the pump handle. It is not sealing the air in as you push it in. Hope this helps.

I have a 425 that I have had to remove the pressure cylinder. I found this on the internet one time, but can't find it again. Anyhow, this is how to remove the pressure cylinder on a Solo 425. Do all the disassembly instructions in the owners manual. Then get a short 2x4 or 2x2 and place it on top on the pressure cylinder through the opening on top of the tank. Then give it a good whack with a hammer. Don't be shy, that ****** is in there. It may take more than one whack. Once you have the cylinder out there is a screen on the cylinder that must be cleaned. To re-assemble, turn the sprayer upside down, insert the pressure cylinder, lay the 2x4 across the bottom of the cylinder and use even force (and hammer) to force the cylinder back in. Stop when you get to the O ring seat and you can do the rest by hand, being careful not to pinch the O ring. I have had Solo sprayers for many years and think they are great. But when it seems that when I leave glyphosate (Roundup) in the sprayer it clogs the screen. My hard water may contribute to the problem.