Hey guys, so I have a graco x7 and I have used it many times without a problem. I went to use it on my second round of paint and the hose started to leak between the nut and hose spring. I have an attached picture. I tried replacing the hose and the brand new one did the same thing.
![111166]( "111166")
No idea why and I can’t find anything on it.
Airless paint sprayer hose leak
Justanewbie
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Does the industry all use the same materials at the same standards?
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Bummer, I thought I found a thread that would also fix my problem, I also have the same exact problem as Justanewbie, used it twice with no issues at all, went to use it again and it leaked heavily in the same place on the hose as pictured, not in the threaded area of the nut, just below the threaded nut where it swivels to tighten up at first I thought it split the hose even tho it was new, so I did the same and went and bought a brand new hose for it and it leaked not just leaked but sprayed out the very first time, even used two wrenches to tighten it up,??????
So, let's start at the beginning...
Since these are high PSI connections we need to think about how the sealing is accomplished.
Don't know what kind of sprayer you have but the vast majority have a NPT (National Pipe Taper) thread machined into the fluid section of the pump (where the paint comes out). The fitting that threads into this (male end)must also be NPT. It must have teflon tape, teflon paste or pipe dope applied to the threads before they are threaded together and wrench tightened. You don't need a lot of sealant and only apply it to the male threads. The seal at this connection is made because the two tapered threads are forced together when tightened.
It appears it's the other connection where you guys are having trouble. As Cocomonkeynuts mentioned this is a NPSM thread. This is a type of pipe thread but the threads are straight, not tapered. This type of thread requires some other method of sealing. In most cases there would be a accurate taper machined into the other end of the fitting. This mates with an accurate machined taper on your hose fitting. The sealing is accomplished when the 2 tapers mate and are wrench tightened together. These types of connections are extremely common any time fluids under high pressure are being transferred. Take a look at the
![Image]()
![Image]()
images attached. Hope this helps.
Since these are high PSI connections we need to think about how the sealing is accomplished.
Don't know what kind of sprayer you have but the vast majority have a NPT (National Pipe Taper) thread machined into the fluid section of the pump (where the paint comes out). The fitting that threads into this (male end)must also be NPT. It must have teflon tape, teflon paste or pipe dope applied to the threads before they are threaded together and wrench tightened. You don't need a lot of sealant and only apply it to the male threads. The seal at this connection is made because the two tapered threads are forced together when tightened.
It appears it's the other connection where you guys are having trouble. As Cocomonkeynuts mentioned this is a NPSM thread. This is a type of pipe thread but the threads are straight, not tapered. This type of thread requires some other method of sealing. In most cases there would be a accurate taper machined into the other end of the fitting. This mates with an accurate machined taper on your hose fitting. The sealing is accomplished when the 2 tapers mate and are wrench tightened together. These types of connections are extremely common any time fluids under high pressure are being transferred. Take a look at the
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Yes its a very common problem if you don't keep the tip guards/diffuser threads clean too. Old dirty threads I take a brass brush to them before reconnecting. Generally hose connections shouldn't need PTFE tape but I use it to facilitate future servicing or I will use regular bearing grease
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Soak em overnight/ couple days with some diluted sodium hydroxide then get a brass brush attachment for a drill, cleans those threads right up. then just make sure the gasket is good
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Here's what you have to do...
Inside the nut is a cylinder / male shaped fitting that should snugly fit into the female fitting *before you tighten the bolt". In order to ensure a snug fit you have to manually connect the cylinder fitting inside of the bolt while screwing the bolt in which seals the connection.
You can manually connect it with your right hand while you hold the bolt to the thread with your left hand and when the cylinder fitting is tight against the female fitting slowly turn the bolt and the seal with take.
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you are not understanding where it is leaking. it not at the nut that attaches to the gun or the pump. it is leaking at the swivel part after the nut. you can't put any sealer on this connection. it is suppose to tighten up when you attach the hose, but this is where it leaks no matter how tight the nut is.
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Tried with the two wrench tightening but i think the hose ends are already wrecked. New outlet fitting is on its way but the flare on the existing one appears to be smooth. Maybe i over tightened it?
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