Topeak’s JoeBlow pump has a flaw

Stripped threads in aluminum base caused JoeBlow pump to fail. Poor design.

(Update, July 20, 2021: I didn’t say how my operation turned out because I wanted to give the pump time to recover fully. Like people, pumps need time to settle in after an overhaul/disassembly. The operation was a success. The pump works as well as can be expected for its age. It’s suitable as a back-up pump.)

I’ve been using the JoeBlow Sport pump since around 2000, and it has been a workhorse. The only other floor pump I owned was a Silca.

The Silca got old and died, which happens to all pumps. It served me well for about 20 years.

I bought the JoeBlow Sport III and now I wish I hadn’t. I should have bought a Park or Levitan. They support their product with replacement parts and show how to maintain them on YouTube. Topeak, not so much.

But on to the flaw. My floor pump failed for a simple reason. The base plate is held by three socket-cap screws. They’re too small for the job.

My new JoeBlow has the same problem, puny bolts, and it looks like the design has not changed in 20 years. I tightened them down, and they needed it, even though the pump was new.

Before I go any farther, to get the most life out of those screws tighten them every few months or so with an allen key. They need to be tight. Had I known when I bought the pump, I probably wouldn’t be writing this column.

The screws keep the floor plate attached to the tube. Standing on the floor plate and jerking on the pump when inflating strains the screws,

Now for a deep dive that explains how to fix the problem. Only do this if your pump’s screws are stripped out and you have nothing to lose.

I know about tapping stripped threads, but I’ve never tried it. Adam Savage of MythBusters fame has a fun and educational guide on how to tap threads on YouTube.

The part that needs tapping is the round plug that sits inside the base of the pump tube. It’s machined aluminum. Aluminum is much softer than steel bolts, so it’s easy to see why the hole threads stripped.

JoeBlow sport pump disassembled, minus the base plate.

After checking the bolt diameter, it turned out that a 1/4 inch 20 (thread count) one inch socket cap screw would work, barely. I say barely because the aluminum plug and its holes are perilously close to the outside edge.

I pressed on because I had nothing to lose. My tapping experience went as well as could be expected for a newbie. I didn’t break the tap and the threads were as vertical as I could make them. That’s crucial. They need to be vertical.

Before you tap, be sure you tap in the right direction. The aluminum disk has a raised lip that faces down. An O ring rests in the lip notch inside the base of the tube. Drill up, the screw’s orientation.

Topeak uses screws with only a small amount of thread. The rest of the screw is smooth. I didn’t find anything like it, so I had to tap the pressure gauge plastic and the base plate, both trivial but be sure they’re as vertical as possible because the thread goes through three parts. Using fully threaded screws makes for a much stronger base.

I purchased the Azuno 17-piece tap and die set in US standard thread measurement. English is less expensive and parts are more readily available than metric.

Note that not all taps are alike. Ideally, you would use a tap that begins its threads at the tip. The Azuno has a void area at the tip. That meant I had to drill clean through the aluminum disk. I don’t think it matters. I can’t imagine air escaping through the threaded screw. If you’re concerned, plug the holes with something.

Disassembly and assembly of the pump is a pain. Removing the pump shaft requires using a screwdriver to press in a plastic tab in two holes at the top of the pump shaft, hidden by a piece of plastic. It’s a terrible design. (That was 20 years ago. The new pump doesn’t use that design today.)

Getting out the aluminum disk requires a long stick or pole. Another O ring sits loose on top of the aluminum disk. Weird.

While you’re at it, clean and lubricate the parts, using heavy oil, but not car grease.

A one-inch screw will work better than the 6/8″ screw length the pump comes with. That’s another reason the Topeak base screws failed. They had only five or six threads in the aluminum. Terrible engineering.

After going through this nonsense, I realize that Topeak’s product offering is inferior to other pumps on the market. I’m not saying they’re terrible, just mediocre. Lesson learned.

5 Responses to “Topeak’s JoeBlow pump has a flaw”

  1. jamesRides Says:

    You might also want to try some thread locker – (loctite red or equivalent) given you don’t want the bolts to come out again. Problem with steel bolts into aluminum is that it is real easy to strip the threads due to overtightening. The bolts will come loose again.

  2. Robert Neff Says:

    I finally came to terms with the Topeak pump head (one of those Presta or Shraeder designs that works great for a few months, then does not. First, got the free replacement, then it failed to do Shraeder again. I finally took all the Shraeder bits out, and now it is Presta Only, and I used that pump head to replace the one on my Silca.

  3. Cathy Switzer Says:

    Thanks! Immediately looked at my Specialized AirTool – yup, tightened up 5 of the 6 bolts. Only 5, because one is already missing 🙁

  4. Luns Tee Says:

    I imagine Topeak no better or worse than many of the other pumps out there. As I understand it, practically all pumps now, regardless of brand are made by either Giyo or Beto, and any of them could share the same flaw.

    Even current Silca pumps are no exception, and I suspect the current made-in-Taiwan Pista and Pista plus may well share genes with your Topeak. What’s a disc for your pump is a taller cylinder they call the piston barrel coupler, but the arrangement of three bolts into this piece clamping the bottom of the barrel to the base plate seems too similar to be coincidence. It wouldn’t surprise me if this coupler is also aluminum and prone to strip the same as what you experienced. They do have a brass rather than plastic midpiece for the outlet/gauge – perhaps the extra stiffness helps keep the bolts from working themselves loose.

    My Italian Silcas’ (~1988 and ~2003) barrels have steel bottoms that are either brazed or welded in place before painting. Bolts are still nice and tight on both of them. I’m curious, what was the fate of your previous Silca pump? Short of running over the barrel with a car, or maybe breaking the foot as sometimes happens, there doesn’t seem to be much that can’t be fixed with them.

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