• skulblaka@sh.itjust.works
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    2 days ago

    If it were up to me to do so, I’d remove the valve core to let the tire vent some pressure. Might still recommend some safety glasses for it though because if you don’t have a good grip on that core it’s going to fire itself out of the valve stem like an air rifle pellet.

    If you don’t have a valve core removal tool then you can also just press down on the tip of the valve core with a small screwdriver or something, but you might be risking some damage to the core doing that, and you’re going to be sitting there an awful long time listening to it psssshhhh its way back down to 30. Even if you do damage the core it’s nothing that isn’t fixable at a tire shop though.

    • Mpatch@lemmy.world
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      2 days ago

      DO NOT TRY TO REMOVE THE VALVE CORE AT THOSE PRESSURES.

      Just do the push thing. One slip and that core at best is lost at worst injures you or a bystander. They are finicky as hell when you get to the last few threads.

      Also, the higher the pressure is, the faster it will deflate. It won’t take that long. Plus, if you do decide to pull the core. At 90psi air rushing out from a small orifice like that is loud enough to cause hearing damage.

      Slow controled release of pressures is the standard procedure for any pressure vessel. Be it a tire at 90psi, a radiator at 15psi, hydraulic excavator at 5000psi, or a fuel injection pump at 30,000psi.

      • skulblaka@sh.itjust.works
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        2 days ago

        This is good advice.

        I didn’t figure 90PSI to be all that dangerous, we use a cheetah tank at my job sometimes for seating tires and that fires at 120PSI, but it’s through a much larger orifice - so it wouldn’t be as loud as through the valve stem. Losing the valve core is also a real possibility.

        I, a professional dumbass and mechanic, would probably pull the cores at any pressure up to but definitely not exceeding 100, and may very well regret my decision to do so. Any normal people who value their safety and don’t deal with tires on a daily basis, and don’t have a stash of a thousand spare valve stems 20 feet away, should exercise more caution.

        Thanks for calling me out on that, I probably don’t respect lowish high pressures as much as I should. I’ll try to keep an eye on that (from behind my safety glasses).

        • Mpatch@lemmy.world
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          2 days ago

          Yeah, I learned the hard way about pressures and what they can do. Not as hard as others mind you.

          I started as a mechanic. Used to have a blast with the cheetah. Hell, I used one to clear out a blocked storm drain one time. That was hella fun. I do a lot of hydraulics now. Around the 90-100psi, you start to run the risk of injection injury, too. Not likely but possible. That’s why they have the safety tips on the blow guns. If the back pressure builds up over 25psi or something, the rubber let’s off and let’s the air by pass. Had a co worker loose a thumb with a paint sprayer. Got to close with the hand he had thick ass leather gloves too. Unlucky I wasn’t there when it happened. probably could have saved it if I rushed him off the e.r sooner but he didn’t know then what hydraulic injection is about and brushed it off. He showed me the next day and told me about it. Boy I near threw him over my shoulder and dragged him to get there faster.

      • dejected_warp_core@lemmy.world
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        2 days ago

        You may also want to push on the valve-stem push valve with a “jesus stick”. This is literally “I wouldn’t touch that with a ten-foot-pole” territory, so go find an eleven foot one with a sharp point at the end.