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I decided to take apart a Bontrager reCharger floor pump recently on a whim, one of those whims during which you pay no attention at all to what you're doing. After putting it back together, the pump now admits air so that when connected to a full tyre the handle goes all the way up by itself.

Looking both here and at manufacturers making more serviceable models reveals the existence of one-way check valves within the pump itself to prevent air escaping from the tyre. Never thought about this and had always assumed it was either handled by the inner tube valve or some magic in the pump connector.

What do these check valves look like and where are they typically in a pump? If anyone knows the answer to this specifically for the Bontrager reCharger, or would be willing to spend two minutes taking theirs apart more carefully than I did to look, then that would also be very useful. I have a feeling something went boing and I'll find it under a skirting board in a few years time.

There are also some genius solutions out there which I might have to try.

Thanks

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    Pretty much every standard pump has two valves, one on the inlet and one at the outlet. The inlet valve is often built into the piston, while the outlet valve is typically either at the hose connection to the pump or in the chuck.
    – Daniel R Hicks
    Apr 15, 2020 at 0:01
  • If the pump is used for Presta/Sclaverand/bicycle valves, there is no need for an outlet valve in the pump as the valve on the tube prevents the pumped-in air from escaping. With the Schrader/car valve the approach is different. The chuck of the pump pushes the valve open and without an extra valve either in the chuck or the pump all air from the tyre would escape back through the pump.
    – Carel
    Apr 15, 2020 at 7:43
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    I managed to fix it! The only valve like thing I could find in the pump was a small bit of brass tubing, but it was hollow all the way through so figured there must a small ball that is displaced when air goes in to the tyre but falls back preventing air going the other way. My partner miraculously found it in the sink. It look like this.
    – plodsmeade
    Apr 15, 2020 at 12:37
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    ...Sorry it look like this. It goes in the base here.
    – plodsmeade
    Apr 15, 2020 at 12:44

2 Answers 2

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I managed to fix it! The only valve like thing I could find in the pump was a small bit of brass tubing, but it was hollow all the way through so figured there must a small ball that is displaced when air goes in to the tyre but falls back preventing air going the other way. My partner miraculously found it in the sink. It looks like this:

check valve

It goes in the base here:

enter image description here

On top of that goes the metal tube that runs up the side of the piston tube:

enter image description here

Thanks for the replies. I love it when I manage to fix the consequences of my own idiocy.

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  • Rephrasing the last line more positively - you managed to recover sucessfully from a situation where not all of the details were known. An expert knows these things already, you're becoming more-expert by learning each new thing.... which is how the expert got there in the first place !!
    – Criggie ♦
    Jan 14, 2022 at 0:47
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This is exactly my story, except that mine was a junked Pedros Prestige pump, exactly the same, that I was trying to fix, albeit absentmindedly, so I didn't notice the peppercorn that fell out. At least I think it's a peppercorn, a large hairy one, that someone had apparently tried to replace the ball with for unknown reasons. I had no idea that it was even involved in my saga until I found your post after repeated deep searches for any clues as to what I was missing. So thanks for the post. As you know, there is absolutely nothing regarding this pump's interior anywhere on line, no schematics, pictures, nothing. But I know a lot more about various bike pumps now than when I started, for what that's worth. I'm using an appropriately sized wheel bearing until a properly sized rubber ball turns up. Thanks again.

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  • The bearing ball will probably work quite well. The main problem will be seat wear, but that will take decades. Great work and welcome to the site. Remember to browse the tour to learn how SE works - it's a bit different to most websites.
    – Criggie ♦
    Jan 14, 2022 at 0:45
  • Hi, welcome to bicycles. Since this doesn't help describe anything about the check valve (except that it must include some kind of a ball) it doesn't really answer the question. Please only post answers that actually, and as completely as possible, answer the question.
    – DavidW
    Jan 14, 2022 at 18:29

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