Whenever we unplug our air pump to our resivoir, all the air comes out. How to fix?

Our pnumatics work when the pump is connected, but the second we take it off all the air comes out. We know our mogo works but we can’t drive around since we always have to connect the pump atm

You’ll always lose some amount of air when you pull your pump, it’s just a matter of practicing a good technique to pull away the nozzle to lose the least amount of air as possible. I usually pump to about 107 PSI since the amount I lose from pulling out and then turning my robot on will put me at basically 100 PSI. For pulling the nozzle out, it may depend from pump to pump, but I’ve found that pulling on it a little before releasing it helps for a quick release.

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All of our air drains out, its fine with the pump but the second we take it off everything goes

Are you sure you don’t have any leeks in your system? Are there any places where the tubing might be pulled too taught, fittings aren’t in correctly, etc.?

Worlds will be strictly enforced do that way no pumping over 100PSI will take place so don’t count on being able to do this at worlds.

@JustKidding I suggest that you try and screw the pump on little as possible and that you try and remove the pump while pumping (when you reach 100 PSI). Also if you have 2 tank fittings try replacing your currently used pneumatic fitting with it.


Do you have teflon tape around the schrader valve?

Is there a way to even enforce that (other than literally watching teams pump their pneumatics)? If I pumped to 102 and lost 2-3 PSI on the pull, when they go to check my PSI it would read 99-100, right?

Usually @kmmohn posts this.


Technically, rule R25 reads.

Pneumatic devices may only be charged to a maximum of 100 psi

So no it would not be legal.


No there isn’t another way, they will literally watch you pump.

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One way to not lose any air is to utilize a schrader valve to 4mm fitting adapter (image stolen from an earlier forum post)

Essentially, you use use a T fitting to connect two reservoirs. Then, you connect a flow switch to the third side of the T fitting like this (red is T fitting, purple is switch)

When you want to pump air, simply plug the schrader valve into the other side of the switch, pressurize, close the switch, then remove the valve. Since all the air is locked in the system the moment the switch is closed, no air will be lost during removal.

There is also the added benefit that the switch can act as an exhaust port. You can place the flow switch anywhere on the bot, meaning you can place your reservoirs anywhere without needing to worry about having to reach the valve.


Some teams in my organization (including my own) use a similar method. Instead of the Schrader we use a weird different piece that connects to the air pump and converts it to 2 vex tubes. Some teams zip tie one end so they don’t lose air and use the same switch method. One difference is that they don’t use t connectors and instead plug one air tank into the other.

You can buy a quick release adapter on amazon for about $30. All you do is stick it onto the schrader valve and then press a button to release from the valve. It does cost a bit but makes pumping a lot easier.


It sounds like the pin in the middle of the valve is stuck down. This pin is pressed down when connecting the pump and opens to let the air in whilst pumping. When you remove it, it should spring back up and seal the valve, but it sounds like this is not happening if all the air then escapes.


In case anyone wants the forum post @Ryan_4253B mentioned, its here

Another thing to check if the fill valve will not hold air is if the valve core is loose (slime has a good description of a valve core).

You will need a tool (called a ‘valve core tool’) to tighten it if it is loose. These have a round shaft that fits inside the valve with a slot in the end to turn the valve core. They can be found at auto parts stores. The valve core is threaded in just like a screw (righty-tighty, left-loosey). If it is loose, that could certainly explain a failure to hold air. If it is damaged, you should be able to replace the valve core (they can also be found at auto parts stores).

Good luck!


Our team uses this inflator which has worked very well for us and will fill to a preset pressure. We had major issues leaking when we removed it at first, but then we added the nut from a pressure regulator onto the valve stem which completely fixed the issue. The nut holds the pump air chuck in just the right position that lifting the lever disengages the pin before the seal is broken. I have also tested that the nut also works with the Ryobi inflator, but it has interfered with a bicycle pump I tried so your millage may vary. You should have the right nut if you have a pressure regulator so it’s a very easy thing to try


Make sure you do not plug the air pump to far on the resevoir or to less, it has to be the perfect balance of distance for it to not release all the air.

Good to know, thanks!

we put the pump only half way on the valve, so when we open the lock the air forces it off and we only loose 2-3 psi