The C654e and C754e or their black and white counterparts have large capacity trays for the bottom two trays. Tray 3 can hold 1500 sheets of 80gsm and tray 4 1000. The trays are position side by side with tray 3 on the left so to get paper from tray 3 to the vertical feed path on the right of the machine a hozontal transport unit is fitted above tray 4. This is why tray 4 is smaller.
J-1730 jams in this horizontal transport unit are just the same as jams at the vertical feed and mean that while paper pick-up was good there was a problem with the paper feed or separation rollers. So first thing is to change the worn looking feed and separation rollers. Easy.
Still jamming.
When removing the jammed paper I can see that the paper has not yet entered the horizontal transport unit so the problem must be in the feed station. There are a set of horizontal feed rollers in the feed station itself so I pull the cover off to have a look but didn't find anything suspicious. While the cover was off I removed the feed sensor actuator to have a look to see if the sensor was dusty. This is what I found:
I had a look at the paper that had jammed and could see marks on the edge at the position of the sensor. Next I manually feed paper into the sensor to see if it would catch on the groove. Yes it does.
It seems that paper hitting the actuator at the exact same spot 200 thousand odd times had worn a groove that was causing the jams. Strange that I had not seen this before. But I had never looked for this before either. I will now.
I sanded and polished the face of the actuator and ran some paper through the machine from tray 3 and could no longer get it to jam so I will definitely need to remember this.
