Sputtering water flow in vevor compressor.
- Thread starter MrP
- Start date
I took it apart and unscrewed the high psi chamber (small pipe screwed into the head inside water jacket) ir seemed like the gasket material, (which was red high temp) wasn't enough on threads. It was difficult getting it out of head because its sealant, but after working a while lt came out. I put new sealant in, replaced o rings and still have the same problem.
I know I didn't wait long enough for gasket to seal. ( I knew better, but got impatient) the way I see it is it can only be three different problems. It's the high psi sealant on the stem I mentioned. Or the seals ( most likely but hard to believe) on the piston rod for the high psi. Or a crack internally between the water fow hole and the head. If I run it for close to ten minutes I can get 3700 psi which is enough for two shots in the Umarex 51 cal. Carbine. I'm waiting until after season to take the high psi seals off and replace because the stem is brass and I will most definitely mar it taking apart and run the risk of destroying it. I will post my progress for you when I do it
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I also keep the water running to help cooling after pump is off. No sputtering obviously at that point.I took it apart and unscrewed the high psi chamber (small pipe screwed into the head inside water jacket) ir seemed like the gasket material, (which was red high temp) wasn't enough on threads. It was difficult getting it out of head because its sealant, but after working a while lt came out. I put new sealant in, replaced o rings and still have the same problem.
I know I didn't wait long enough for gasket to seal. ( I knew better, but got impatient) the way I see it is it can only be three different problems. It's the high psi sealant on the stem I mentioned. Or the seals ( most likely but hard to believe) on the piston rod for the high psi. Or a crack internally between the water fow hole and the head. If I run it for close to ten minutes I can get 3700 psi which is enough for two shots in the Umarex 51 cal. Carbine. I'm waiting until after season to take the high psi seals off and replace because the stem is brass and I will most definitely mar it taking apart and run the risk of destroying it. I will post my progress for you when I do it
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Can you purge the cooling system completely of water and then put some hoses on each end of the compressors cooling circuit and then submerge them in a cup of water and then start compressor briefly ? If the lines bubble in the cup of water, you know you have a leak from compression side to cooling side. Obviously, don’trun the compressor very long without cooling water.
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The vevor uses a screw to hold the hi pressure seal/ring in and it's not like the Yong heng piston seals.
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What I see when apart is the large piston on the bottom and a skinny brass rod with 3 teflon seals coming out of the big piston. I think I have to unscrew the brass rod at the top to slide the seals off. That's what I am going to try anyway. I just don't want to damage anything to bad. I figured if the top of the brass high pressure rod unscrews from the top i can sand or file the marks i may make in it. Im hoping it comes apart there, I can't imagine it any other way.
It definitely is leaking in the high pressure sleeve where it screws into the head. Or the seals on the high pressure rod. I can still use it but it's not right and I can't get more than 3500 psi+/- in the gun. Im not worried about the coolant chamber over pressuring because of the amount of air leaking into the water pump. I just run it for a bit and keep a eye on the temp with my laser temp gun. Once it gets to about 70f I stop and let the water cycle until it cools and then do it again. I just don't want to tear into it to far now because it's hunting season and the nearest airgun/ fill store is a 45 minute drive one way.
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Im new to all this and appreciate everything anyone adds. I also would like to get a good high power .25 cal pistol that's reasonable money wise if you could help point me in a direction. Thanks
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Does the top of the brass HP stem unscrew or do I have to take the lower end off and unscrew a bolt hidden under big piston?
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I fixed the leak. But broke the hi psi rod. Lol. Well it was leaking from where I expected it was, but thought I had done enough to seal it. Apparently not.
Leak causing sputtering was the threads either on the head(aluminum top) or thread on the stainless steel sleeve that is the high psi chamber/sleeve for rod seals.
I ended up using the highest pressure jb weld as pipe dope. But I figured I would take the seals off the brass pump rod coming out of the big piston. I thought it unscrewed from top of rod like a cap that went through seals. It doesn't. I broke the brass top off. So now I only have two seals instead of three. Pump will go to 3k psi decently but won't get more pressure. Kinda useless for me because of my big bore but did fix sputtering and runs good.
Leak causing sputtering was the threads either on the head(aluminum top) or thread on the stainless steel sleeve that is the high psi chamber/sleeve for rod seals.
I ended up using the highest pressure jb weld as pipe dope. But I figured I would take the seals off the brass pump rod coming out of the big piston. I thought it unscrewed from top of rod like a cap that went through seals. It doesn't. I broke the brass top off. So now I only have two seals instead of three. Pump will go to 3k psi decently but won't get more pressure. Kinda useless for me because of my big bore but did fix sputtering and runs good.
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I'm not sure if you read what I found to be the problem. Pretty simple fix if you don't destroy anything taking apart. Mine was the stainless steel pipe inside the cooling chamber. It's threads leak causing the sputtering. Vise grips to take the pipe out. Apply high pressure thread sealant. There's a little disc in between the pipe and the head that is easy to miss. Just don't plug the hole obviously. I went further while mine was apart just in case and broke the brass rod top seal off. You won't have to do anything to that. Good luck if you fix it.
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