Noise from drum after first clean - no washers present

Hi,

I’ve just done my first deep clean after around 30–40 roasts. Since cleaning and reassembling, I’ve had a noise that appears to be coming from the front of the roaster.

On initial reassembly, the front bearing wasn’t seated correctly. I powered the machine on briefly before realising (lesson learned). I then corrected this by lifting the shaft from inside so it was properly seated. It roasted fine for a few batches after that, but would occasionally develop a noise, which could be temporarily resolved by gently pushing the shaft from the front while it was turning.

After reading various posts here and on Reddit, I’ve concluded this is likely a front bearing issue, so I’ve ordered a replacement and am awaiting delivery.

One question I’m hoping to clarify:

When watching cleaning/maintenance videos, I’ve noticed washers or shims behind the front bearing. As far as I’m aware, my machine did not have any. There’s a chance one may have fallen out during cleaning without me noticing, but I’m fairly confident there was no washer present.

Is that normal? Should there be a washer/shim behind the front bearing?

Any insight appreciated.

Update: Changed the front bearing. Nothing. Turned the machine on without the chaff collector on - i can hear that the noise is in fact from the rear of the machine. The wear pulley is not, however, chafing.