The O ring in my Schwinn hand bike pump with gauge needs to be replaced. Schwinn is of no help and Ace Hardware doesn't have the right size (she thinks the size is particular to the company). Does anyone know what the size of the O ring is or where I could get one? Ridiculous that the whole pump needs to be tossed when a part will fix it right. Sigh.

Thanks.

If you have the old one, you should be able to measure and come close to the correct size. If you have some calipers, then measure the inside diameter of the groove it sits in. Then the width of the groove. And compare to the same measurements of the old O-ring itself.

Not sure why Ace didn't have a size to fit. But try auto parts stores or browse the world wide web. Although it might be the cylinder walls are worn or some light grease on the ring and cylinder walls or something else is needed also if you actually tried some you thought might fit.

If this is a unique shape and not a round or square cross section, then there might be more to it.

My 2¢. Buy a new pump and be done with it. Fiddling with stuff takes time you could be out cycling.

Metric?
Will a smaller diameter stretched work?
Maybe the one you have has stretched and/or swollen from a non compatible lube?

Look for an industrial supply store that services/sells hydraulic pumps etc.
They should have oodles of size charts/expertise.

have you tried putting some very light grease on the old o-ring yet?
clean the bore and piston, lightly grease the o-ring and bore, put the pump back together, and give it a test.

Unfortunately anything modern Schwinn was designed to be disposable, it is part of their "Quality" initiative. The light grease could work or going to a place that sells more o-rings like industrial supply is probably the best bet if Schwinn can't help.

I guess I really needed to be super obvious specific. I WENT to Ace and other hardware places. I stood there and tried on the sizes that seemed to agree using eye scan. They fit, but not properly enough to make the suction noise when I gave the pump a fake pump to know it was perfect. I went outside and pumped the tire with that first O ring I thought was a perfect fit even tho it didn't make the suction noise. It DIDN'T pump.

I do not belong to your throw-away perfectly good products that in any other country would and could be fixed mentality.

I live on my bike. Thus, I get plenty of riding in and searching for an O ring is not wasting riding time.

I will continue my search.

I don't throw things away either. That just means they go to a land fill where they'll stay virtually forever and be of no use to anyone. I take them where they can be recycled.

Your pump isn't perfectly good. As evidenced by your need to find a new O-ring. And in todays consumerism, sometimes just getting a new thing, and properly disposing of the old is the better thing to do.

For certain there probably is a O-ring for it. But are you certain the O-ring is the only thing wrong with it. Check valves and other methods of letting supply or new air get into the pump cylinder as well as keeping air already pumped into tires with Schrader valves can be at fault to. Many of the good brands of pumps offer rebuild kits. But Schwinn is long out of business. At least as it was prior to the mid 1990's.

But if fixing it is what you want to do, there is no need to get all high and mighty sounding. As you can see, I do that well myself.

If you are in a area that has a lot of industry, then there are likely suppliers for that industry there that will have all sorts of O-rings. Granger might be one of them. But whether they'll have staff that want to hunt for hours for a single O-ring that only cost them ½ ¢ or less is another question.

You didn't memtion an Industrial Supply place like I mentioned in my post.
They have a LOT more stuff than a mom & pop place.
Did they have an O Ring sizing cone?


EDIT-
I just googled "O" ring and my approx. location, scrolled a bit and found a place with all kinds of rubber seals/O rings.
https://www.applied.com/search/?sear...ll&text=O+ring

did you apply a small amount of light grease to the o-ring, piston, and bore ? have you CLEANED the bore and piston?

O-rings are sized by ID and thickness. If you get some calipers, take some measurements, post them up here, along with photos, maybe someone can help you? I do a lot of O-ring work for different products, and have some understanding on how to size them. The issue you will have, though, is finding a place to sell you just one or two. Industrial supply houses don't make money that way, so you may need to buy a pack.

Regarding serviceability, that costs money. A pump will last for a good long time on the original seal, and there is not much of a business case for a manufacturer to stock service parts for a cheap pump. Even parts like Shimano are either hard to find, or non existant after some years. No sense in fighting it.