Ben Gottemoller

Hi Charles, That unfortunately looks like a stripped main drive gear all the way inside the gearbox. Your grinder looks fairly new so you might call Breville to see if it’s still under warranty. Drive gears are unfortunately hard to come by. There is a source on ebay however it is way overpriced in my opinion. Another user above mentioned 3D printing one, however I am not sure what model he used and what the durability is.

Hi Rick, Hmm, I only cover the BCG800XL and the BCG600SIL in the videos. The BCG820 is a newer design with internal changes to the impeller (steel cladding) and the drive shaft. The 3D printed replacement will not fit that model unfortunately. That said, with the 820 it is possible to remove the impeller without significant disassembly since it is smaller. It should not harm anything to take it out and put it back the way you did, and the lack of a felt ring is fine too. Regarding how to proceed: It may be possible to bend the steel fins on the BCG820 impeller, so that they protrude slightly further. This idea is untested, and I make no guarantees, however is an option to potentially try.

Unfortunately sanding on the impeller will only make the grind coarser. It will cause the lower burr to sit even lower, resulting in a larger gap with the upper burr. Two thoughts:

When you first started and the burrs were too close and even touching — could it have worn down the burrs?

I can’t stress enough that the lower burr and lip on the drive shaft is the best reference for knowing that the lower burr is the correct height. Usually sanding the impeller is not necessary and I am wondering if now that it has broken in the sanding took too much off.

BCG800XL Grinder Jamming due to Worn Impeller

In any case the modification to support extra grind range is probably worth a shot. I have used if for two years now — nearly all espresso — and the only real caveat is to listen for the burrs touching so you never go to far.

BCG800XL Grinder Jamming due to Worn Impeller

Thanks for writing. Problems #2 and #3 may all be due to the same issue of the burr spacing. When it runs too coarse it can grind a LOT more beans in the same amount of time. The finer you go the more the torrent of grounds becomes a trickle. I would first check the *lower burr* alignment and closely compare with the illustration here: BCG800XL Grinder Jamming due to Worn Impeller

Only after that begin trying to adjust the *upper burr* adjustment gear. If the alignment got messed up it will take a bit of experimenting to get right again. As the big gear rotates it moves the upper burr carrier (gray cylinder) up and down. BCG800XL Grinder Jamming due to Worn Impeller

Oh no. We used to have a good soure for that gear over at forumappliances.com but they no longer carry it. Ebay has it if you search “Breville main gear”. Unfortunately it is way overpriced in my opinion. You could try contacting the seller to see if they will come down. Might be cheaper to buy another broken BCG800XL on ebay and salvage a gear out of it (as long as it too does not have the same issue).

Congrats Stacy! Enjoy your coffee.

Hi Miles,

It may just be tolerance stack-up that occasionally results in this. Even a <0.5mm difference in burr spacing could do it. I think the comment here will help you make the adjustment to get the grind you want:

BCG600SIL Dose Control Pro Coffee Grinder - Jamming due to Worn Impeller

One other thought also: Check the fineness of the grind. Could it be finer than you had ever gone before? If the grind is ultra-fine, it can become like a paste and clog the grinder that way. If it’s tough to tell by feel or look of the grounds, you can probably tell this way too: Fill your portafilter, grinding by weight (eg: 18g for a double shot). Then tamp normally, and attempt to pull a standard 9-bar shot. If it fails to give more than a trickle then it is probably too fine.

Then it becomes a question of whether the lower burr is too high or the upper burr needs elevation ring adjustment.

Double check that the lower burr is not sitting too high using the images here:

BCG600SIL Dose Control Pro Coffee Grinder - Jamming due to Worn Impeller

Hi David,

Thanks for posting. Any chance this is a really dark roast? These can be super oily and cause issues. I have a writeup on this over on the BCG800 page here:

BCG800XL Grinder Jamming due to Worn Impeller

In that case it’s not static but momentum, since the high amount of coffee oils cause large clumping and these tend to maintain their angular momentum when exiting the chute. In that case water might even make the issue worse. Perhaps try a medium or light roast to evaluate if this idea is on track. Cheers.

Nice job Robco. Good to know some units only have one washer as well. Maybe at the factory Breville varies it based on tolerance stack up. In any event glad you got it all fixed up and enjoy your coffee.