I printed it… and i did not see the same difference (that is very extreme xD) but BTW… that printing like a charm. Maybe as another said in comment (on printables or thingiverse) : i did know that i have this trouble before to fix it. That is probably my best upgrade of my SV08 (ratio cost/efficacity).
There’s an “extruder gear fix” that was designed by a woman on a Facebook group for this exact problem. I printed the most current version she posted on 11/11/24 and it worked great. I’m posting the link below for anyone who needs it. Works great!
That link is already posted above, but it doesn’t hurt anything to post in again. 
I did not see the link posted just a reference to something close to it by name. Or it’s just not showing up on my phone. Either way, it’s here for sure now. Edit: and I just looked again and now I see it…
Eh eh, at the same time, it deserves to be better known
I’m a bit late to the discussion but I ran in to the exact same issue and was gobsmacked about the poor engineering that allows the idler gear shaft to slip out of position. There are actually two holes for 2.5mm grub screws to fixate the gear on the shaft, but there are no screws in them.
As I happen to not have the matching screws lying around I turned to a pragmatic solution and printed a small part that will keep it in place. No disassembling (apart from the removal of the toolhead cover) or additional tools or screws needed. Find photos and .stp file attached, I hope it is helpful.
20250525_tensioner-clip_v2.stp (554,1 KB)
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Thanks so much! After a week of trial and error and complete confusion, this little thing immidiately solved my troubles.
I’d already installed the Valerie Moore anti-walk idler gear axis spacer on my SV08 a long time ago, after the extruder stopped feeding, but just had the extruder idler pulley pivot axis walk out on my Zero. At first I thought I had a nozzle clog, because I’d recently switched to a 0.2 mm nozzle, but after verifying that wasn’t the problem, I noticed that the extrusion went from constant extreme under extrusion to intermittent extrusion after I checked the idle pulley tensioner. It would weakly extrude for a few seconds and then not extrude for a few seconds. I disabled the motors and turned the extruder wheel by hand, and it would extrude for three rotations and not extrude, slipping on the filament for three rotations (it uses a planetary gear reduction).
I pushed the idler pulley axis back in place and restarted my print. I noticed the idler pulley gear has the same two holes for set screws as the drive gear, apparently using the same part for both, but the set screws aren’t used on the idler gear. I momentarily considered using those to secure the idler gear to the shaft but realized the shaft was a press fit into the plastic on the ends, so the idler pulley needs to rotate on the shaft. I’ll print a spacer to keep the idler pulley shaft from walking out again, and I’ll write it up over in the Zero forum so it’ll be easier for people to find, both here in the Sovol forum and when searching the internet.
I’m disappointed that this same design flaw from the SV08 extruder that reduces reliability wasn’t corrected when the Zero extruder was designed. I suppose this is a problem on the SV08 Max as well? This is a simple fix that Sovol needs to make to improve reliability and customer satisfaction.
It would also be nice if Sovol (actually all 3D printer manufacturers) would use a partially threaded thumb screw for the idle pulley tensioner. The full length threads catch on the washer and spring and bind the idle pulley tensioner. This is another simple fix that would greatly improve the reliability and user experience. The clunky and crunchy idle tension adjustment really bugs me. I might grab the thumb screws from all of my printers, chuck each in the mini lathe, and remove the threads, although a full diameter unthreaded shaft would be a better solution.
It seems to me that the suggestions in the previous post are very constructive.
