Replacement for Valve Stem in the new V5 pneumatics kit?

So instead of having the Schrader valve directly mounted to the reservoir, you can install a fitting of any type (hence why I said “straight or angled”) on the tank, connect a tube to it, and then on the other end of that tube connect the remote fill Shrader valve that I linked in my post. You’ll probably need to block off the other port on the valve.

This way, when you put air into the valve, it flows through the connected tube into the tank and pressurizes the tank.

I only have the old kits unfortunately, but the configuration would look something like this:

I’m sure @mbeem or someone else from VEX can send a picture of what a setup using the correct components would look like.

Separately is there any update on an ETA for replacement parts? If not, in the mean time would VEX consider stocking the above SMC remote fill valve as a temporary measure?


Created an account to say our team had the exact same thing happen this week. Not sure if there is a better way to log these issues so vex can track number of occurrences?

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yes there is a better way! contact VEX support - vexforum is a discussion area, not really best way for VEX to track issues …


Contacting VEX support for broken / replacement items is always your first goto. All we can really do is go “yep, it’s broken”


Adding the link to the Legal Pneumatics article in the STEM Library and the link to the legal pneumatics list from the 2022-23 season for reference

My team also broke our valve for the new air tank, I tried looking to the discussion but it was confusing, could anyone provide links or some type of reference to any valid valves that fit and are legal. We have tried researching for an M5 valve but most of them don’t seem proper.

See link to STEM library article in my post above yours. In the legacy parts section it provides the SMC parts numbers. These can be purchased through SMC or SMC retailers (ex: Orange Coast).

There are no legal direct replacements currently. So far your best option seems to be to get a remote fill valve from the old kits (available direct from SMC as I’ve linked above), which plugs into the tubing rather than directly into the tank.


Well, I found the part I need(the part that connects the air pump to the new air tank) except nothing is coming up in my search for that specific part. Sorry if I’m kinda dumb, just a new team tryna replace our kit

This isn’t the part that works with the new tank. The new tanks have M5 (much smaller) threads and won’t work with the part in your picture. That part will only work with the old tanks. The valve that screws directly into the new tanks is a fully custom part made by VEX, and there does not appear to be an equivalent available.


The way to fix tis issue would be to contact vex support they can help ou most.

Do you have any update on a timeline for replacement components? The kits are now out of stock so teams aren’t even currently able to buy a whole new kit to replace broken parts.


I replaced the Schrader valve in ours with one just like that goes in the car because it’s the exact same.

Would this not be legal because it is the same part? I also found that it unscrewed on its own, so I put the original back in and tightened it very well.

Can you explain what you meant by this? Did you find an entire replacement valve stem or did you merely replace the valve core?


Ask Official Q&A …

My gut with regards to modifying internal mechanism and structure of pneumatics has been prohibited in previous season, it is likely to be disallowed.

I did not replace the valve stem, I temporarily replaced the Schrader Valve inside of the valve stem with one the exact same as was in there.

As for this, I can see that. That would make sense but it would also be kinda outrageous to not allow us to replace Schrader valves when they break.


I had the same exact issue. These valve stems are trash. I went through Grainger and Amazon to piece together two parts to replace this.


valve stem:

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do note it might not be considered competition legal.

Had Inspector reject non-identical VEX pneumatics parts this past weekend.

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If you can machine the part from the vrc legal commercially available third party standoff then it should be legal.

Would it be a stretch to say, worthy a conspiracy theory label, that vex intentionally includes custom easy to break parts in their kits to make people buy multiple expensive pneumatic kits?


It seems that this is an issue with many other teams as well, when inflating the canisters to around 120psi during testing this same thing has happened to two of our canisters. Most vex parts are able to be swapped around but the new kits are made with different measurements for some parts, EX: the piston rod being able to screw into a shaft lock piece, which I found out is very helpful for making something stable for the wings. Back to the point, there are many parts online so that you can somewhat fix this issue before Vex releases a repair kit with Vex legal parts. This issue seems to be only with the new canisters so my recommendation is to use the old ones, they are not only rated for higher PSI but we have found them to be useful because they can fit in the middle of our robot longways which saves more room for the intake and lift that we have. Our instructor found some parts online that we can swap it with testing, hopefully. But most likely they will not fit.
Also, the reason why I have seen some of these break is because people twist them on and off to get the pump well, pumping and not leaking air. Thats just my hypothesis though.