Question on JCB 3CX hydraulic fittings

noFace_0

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I have a 1991 JCB 3CX I use for farm work. I've noticed the BSP hose joints include rubber seals inside and now that I'm redoing a set of pipes, I'm questioning if those seals are actually pulling their weight. With pressure this high, I don't want to risk a blowout but at the same time, I don't see why the metal faces wouldn't hold. Has anyone actually tested this side by side, with and without the gasket?
 
Those rubber seals aren't optional. Sure, metal-on-metal can hold for a while, but under 3,000 PSI it's just asking to leak. JCB didn't toss those gaskets in for fun... they're doing the real sealing work. Skip them and you'll be mopping up oil.
 
I have a 1991 JCB 3CX I use for farm work. I've noticed the BSP hose joints include rubber seals inside and now that I'm redoing a set of pipes, I'm questioning if those seals are actually pulling their weight. With pressure this high, I don't want to risk a blowout but at the same time, I don't see why the metal faces wouldn't hold. Has anyone actually tested this side by side, with and without the gasket?
I'm with @Blind_Morgan.. the rubber seals are absolutely crucial and you'd be risking a major leak or blowout without them. The metal-on-metal connection simply can't create a perfect seal on its own, especially with high pressure and vibration. The threads just provide the clamping force, then the seal does the actual work so don't skip them!! Use new ones every time you reconnect a line. They're cheap, and a new seal is a lot easier and safer than cleaning up a hydraulic oil spill or having a line blow while you're operating the machine.
 
I have a 1991 JCB 3CX I use for farm work. I've noticed the BSP hose joints include rubber seals inside and now that I'm redoing a set of pipes, I'm questioning if those seals are actually pulling their weight. With pressure this high, I don't want to risk a blowout but at the same time, I don't see why the metal faces wouldn't hold. Has anyone actually tested this side by side, with and without the gasket?
I'm with the two guys on this.. without that seal, you're relying on metal-on-metal, and even the slightest bit of damage will cause it to weep or fail completely under the strain. That's why using a new seal is the cheapest, most vital insurance you can buy for your hydraulic system!
 
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