C&P 8x12 Oldstyle - audible noise on impression

I’m hoping someone can offer me some insight on zeroing in to what makes my press create a fairly loud clunking sound each time the platen comes in contact with the form when under what I’d consider moderate impression. I fear going with too much deep impression on my press runs as that noise amplifies and becomes a double hit…

1905 8x12 C&P Oldstyle, she’s well levelled off on a very sturdy surface, runs very smoothly and quietly, both with motor/belt and treadle.

I’ve narrowed the source of this audible double “thock” down to the “Large Gear Cam Wheel” area, part no 14, right side of the press. I see a visible movement/tremor in the area, where the the “Side Arm” part no 47 connects to the “Main Shaft” part no 68 and the Large Gear Cam wheel. The Cam wheel is good and snug, no play whatsoever, the side arm is also good and snug.

But I recall having the channel located inside the Large Gear Cam Wheel explained to me by the old-timer that helped me assemble the press (sadly press came partially disassembled by previous owner), and am thinking the “Cam Roller” and “Cam Roller Stud” parts 33 & 33S that run inside this channel may be loosening up. I religiously oil this cam roller through the access hole in the outer face of the Large Gear Cam Wheel each time I’m about to run the press, nevertheless, I’m at a loss on how best to access this to check on how tight it is or not.

Anyone know of a good tip on how to access and tighten the Cam Roller stud without starting to take the side arm and cam wheel off the press?

Grateful for any input, thank you!

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My press, once upon a time, made that “clunk” on the gear side when the key was loose. The issue was the main gear cam wheel (#14) not being centered horizontally on the pinion gear (#13) because the pinion gear key (#13K) was loose.

Hey, good of you to bring this up MayDay, I’m going to check that area out. Some previous owner has hacked off the end of that pinion shaft and removed the steam pulley on my press, too bad as I have to drive the press from the flywheel rather than that pulley as intended. Things people do to these poor presses, probably trying to gain a few inches to fit it in a tight spot in a previous life.
Thanks, will check this out and get back to you all.

listen to the press… A “Ka-Lunk” sound will be a loose pinion key. A more sharp “Bang” is the rocker lock kicking out.
A) loose pinion key prob needs to be replaced. look up gib key at “McMaster Carr” measure your old one. it prob 3/8 x 3/8 x 2 or 3 inches… it needs to be fitted. just tap in lightly and pull out with puller. file down where you see contact patch on key. this is an in depth process. you can contact me for more details.
B) rocker lock kicking out. look up rocker lock in parts manual. this kicks out when too much pressure is put at top of chase/ platen. easiest solution is to lower forme towards center of chase. or low center.