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I have a raw water pump for a boat that has a press fit bronze bushing that goes into the back of the water pump (into a "cap" that attaches to the back of the pump). The water pumps shaft rides inside the bushing. The bore in the cap that the bushing goes into is only open on one end which is how you push the bushing in. Once the bushings in, there is no way to remove it without breaking the bushing. The stock one that came with the pump was some sort of carbon based bushing and meant to be broken with a chisel. I had no problem getting the stock one out. I installed a new one which is bronze. Once I installed it, it seemed to be warped or have some issue because the shaft didn't ride smoothly in it. I ordered a new bushing and shaft, but now I have to remove my old bushing.

The bronze bushing does not break like the old one did. I've spent over an hour trying to carve out the walls of the bushing with a Dremel tool and various bits. It is slow moving, tedious and prone to error because I cannot tell when I go from carving out bronze from the bushing to the bronze in the water pump cap.

I'm looking for suggestions about how to do this better. I've considered using a drill press with increasing sizes of bits or perhaps just using a more appropriate choice of Dremel attachments.

Any ideas?

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Update

This was very difficult to remove and especially to remove without damage. All kinds of Dremel tools (grinders, sanders, cutters, etc.) were used and while they did make "progress" on the material removed, it was impossible to tell where the bushing stopped and the housing started because they were the same material. It ended up taking a center drill to remove it. Luckily my brother owns a custom hot rod shop and has all the tools.

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  • When you installed the new bushing, did you check the fit with the shaft? Did you check the shaft for ovality, concentricity etc
    – Solar Mike
    Commented Sep 22, 2020 at 5:26
  • Have you tried a shop press? If you can support the back side of this and have a suitably-sized insert (try a ratchet socket) a press should be able to develop enough force to press the insert out of the housing.
    – jwh20
    Commented Sep 22, 2020 at 10:11
  • Bronze bushings should be brittle and remove easily with a punch
    – Tony Stewart EE75
    Commented Sep 22, 2020 at 18:32
  • @TonyStewartSunnyskyguyEE75, the bushing was not brittle at all. Sure, more malleable than steel, but even with the majority of the bushing drilled out and only a very fine wall remaining, it still took some muscle to get it out. My understanding is there are different compositions for Bronze and thus you can have different characteristics. The characteristics of this particular bushing was "Devil"
    – Ryan Griffith
    Commented Sep 22, 2020 at 23:40
  • Looks more like brass than Bronze. You”ll want a precision drill press to remove it.
    – Tony Stewart EE75
    Commented Sep 23, 2020 at 0:01

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This a similar setup to a pilot bushing fitting in to a crankshaft. The tried and true method of backyard mechanics involves grease and a wooden dowel. Find a wooden dowel slightly larger than the inside diameter of the bushing. Sand the dowel so it fits snuggly in to the bushing. Pack the bushing full of grease. Insert the dowel and tap it with a hammer. The idea is that the grease will have no where to go and can't compress so it will force the bushing out. Alternatively you can drill it out. Or tap threads into the inside with a bottoming tap. Then either screw in a bolt and use a slide hammer to pull it out or continue screwing the bolt in until the bushing climbs the bolt and comes out.

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