Impeller cleaning problem

A long overdue impeller cleaning was in order, so I loosened the set screw. In fact, I completely removed it. The impeller seems to be spring loaded, but even with the set screw removed, it jams on the shaft after about 0.5 mm of motion. So it’s not frozen, but it also doesn’t want to come off the shaft at all. Any advice out there?

Happens to me too.

That 0.5mm of motion is probably not the fan moving on the axle. For me, it’s the axle moving within the motor. So don’t push/pull too hard!

I recommend dissolving as much of the coffee residue on the axle as you can. I use Cafeiza, I know other people use simplegreen or vinegar or just warm water. Clean the spot where the fan mounts on the axle and maybe put a few drops in the hole where the set screw was.

Then I just wiggle it and pull it gently. Sometimes I push on it from the back using a bamboo skewer. When I do that, I use two hands, one working with the skewer, the other pulling on the cage. I’m not using the skewer to lever/pry the fan out. I have the skewer across the full diameter of the fan, and I try to make the force exactly parallel to the axle.

I worry about bending the metal, so I don’t use a lot of force or leverage. I try a little, turn the fan, try again, repeat. I think mostly what I’m doing is working the cleaning fluid in. Eventually it slips free. Took about 5 minutes yesterday.

I’ve done this a few times over the years and have not warped the fan yet. I think the key is to go slowly and apply force as evenly as possible.

good luck!

( Arrows are where I push/pull. )

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This happens to me each time i deep clean and it is what I dread the most as it gets worse each time, frankly. Last time I did the Cafiza method and still it took a coupe of hours of aggressive prying to get it free. I understand the updated fan may have a larger bore to make this easier- my V2 bullet is three years old, and gets about 2 Kilos through it every 3 weeks.

Try with a a creme brule torch or heat gun to carefully heat up the impeller, but don’t apply too much heat to the shaft directly, then it should come right off.

Thanks, Jacob. I finally got it off. I was afraid of damaging the motor shaft tolerances, but it appears to be OK. The moral of the story is don’t wait too long before cleaning the impeller!


The squirrel cage is aluminum, right? Don’t let it spend a lot of time in a hot Cafiza solution; a few seconds should suffice.

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I find if you clean regularly (e.g. every 20 to 30 roasts in my case is when I do a complete clean) a dilution of 3 parts Simple Green (concentrated) and 2 parts water works pretty well. Spray on liberally and let is “soak” a bit.

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Right! I use cold water and rinse right away. that stuff is powerful and fast