Gene Cafe Drive Motor Cog

The Gene Drum Fails to rotate, possibly with E3 error

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A few recent forum posts have prompted this little article. The problem is an easy one to fix.


"I put the roasting chamber into the machine intending to roast. It switched on then beeped a few times and came up with an E3 error. The handbook suggests a drive failure and I note that the cylinder rotates all the way around quite freely."


Having loading the gene's chamber with greens; placed it back into the unit and started the roasting cycle, the chamber then abruptly stopped. The noise that immediately followed was a grinding type of sound like something had got caught in the mechanism .


In the above pic. situated between the small electric motor and the circuit board there's 3 cogs. You will notice the large familiar black cog paired with a much smaller white cog; just under this cog is very small white cog that is attached directly to the motor and it’s this one that’s at the business end. Unlike the above pic., however, the small cog is my gene is hardly biting the upper cog due to it being out -of- line. It can be quite hard to push on as the users comment shows "I have tried pushing it back in line, but it won't budge and I'm reluctant to apply more pressure for fear of damaging the unit."

I would suggest you initially lever it off completely, simply so you can ensure that it's

1. Not damaged and neither is the larger white cog
2. Lined up properly when you push it on.


If either part is damaged Bella Barista definitely have spares and the new motor cogs have a central brass insert now. They rely on a friction fit and it's possible that the cog gets damaged it starts to run out of line, so check it carefully. If/when you get it back, if it becomes displaced again, then check again for wear causing it to push out of line and replace one or both cogs. The larger white one I think is bought as a set (metal bar and 2 cogs). The parts are very inexpensive.

You can check what you might need using the IPB (Illustrated Parts Breakdown) for the Gene on the Wiki.


is how the forum member fixed the problem, and it's the same method I would use myself, so I have reproduced the text in full.

Fortunately there's no damage to any of the other cogs. A friend of mine, Jimmy who's a dab hand fixing electrical gadgets, found that a simple cotton reel/bobbin and a few light taps with a hammer was all that was needed to get the cog back in position. The hole through the centre of cotton reel is an ideal fit for the cog shaft so when tapped lightly with a hammer, the reel pushed the cog squarely back into position. My friend also removed the small circuit board as a safety measure - this too was a simple process requiring the removal of a few screws and pulling out a couple of connection plugs. Even though there was no problem tapping the cog back into place, my friend did comment that the cog fit its shaft very firmly hence to move as it did must of taken some time.

My gene is over two yrs old and has been used regularly so if anybody experiences a similar problem or as a preventative measure, don't forget to pop a cotton reel into your tool box.

PS. I just spotted the same cog on sale at Bella Barista for 21p so even if the cog gets damaged…

Note: old style cog shown without brass insert…(BB do have the new cogs in stock).